Class
RadDropDownList

Represents a combo box control that displays a list of items from which the user can select. The RadDropDownList class is essentially a wrapper for the RadDropDownListElement component which implements the core UI and logic functionality. This control supports various selection modes, data binding, customization options, and can be integrated with other Telerik controls.

Definition

Namespace:Telerik.WinControls.UI

Assembly:Telerik.WinControls.UI.dll

Syntax:

cs-api-definition
[TelerikToolboxCategory("Data Controls")]
[ComplexBindingProperties("DataSource", "ValueMember")]
[LookupBindingProperties("DataSource", "DisplayMember", "ValueMember", "SelectedValue")]
[DefaultBindingProperty("Text")]
public class RadDropDownList : RadEditorControl, IDropTarget, ISynchronizeInvoke, IWin32Window, IBindableComponent, IComponent, IDisposable, INotifyPropertyChanged, ISupportInitializeNotification, ISupportInitialize, IComponentTreeHandler, ILayoutHandler, IAnalyticsProvider, ISupportRootUIAutomation

Inheritance: objectMarshalByRefObjectComponentControlScrollableControlRadControlRadEditorControlRadDropDownList

Derived Classes: RadCheckedDropDownListRadDomainUpDown

Implements: IAnalyticsProviderIBindableComponentIComponentIComponentTreeHandlerIDisposableIDropTargetILayoutHandlerINotifyPropertyChangedISupportInitializeISupportInitializeNotificationISupportRootUIAutomationISynchronizeInvokeIWin32Window

Inherited Members RadEditorControl.OnParentChanged(EventArgs)RadEditorControl.GetPreferredSize(Size)RadEditorControl.GetRootElementDesiredSize(int, int, int, int)RadEditorControl.SetBoundsCore(int, int, int, int, BoundsSpecified)RadControl.isResizing2RadControl.isDisposing2RadControl.invalidResizeRectRadControl.isAccessibilityRequestedRadControl.Construct()RadControl.CreateBehavior()RadControl.InitializeRootElement(RootRadElement)RadControl.LoadElementTree()RadControl.LoadElementTree(Size)RadControl.OnKeyDown(KeyEventArgs)RadControl.OnKeyUp(KeyEventArgs)RadControl.OnPreviewKeyDown(PreviewKeyDownEventArgs)RadControl.OnKeyPress(KeyPressEventArgs)RadControl.OnClick(EventArgs)RadControl.OnDoubleClick(EventArgs)RadControl.OnMouseDown(MouseEventArgs)RadControl.OnMouseUp(MouseEventArgs)RadControl.OnMouseEnter(EventArgs)RadControl.OnMouseLeave(EventArgs)RadControl.OnMouseMove(MouseEventArgs)RadControl.OnMouseHover(EventArgs)RadControl.OnMouseWheel(MouseEventArgs)RadControl.OnMouseCaptureChanged(EventArgs)RadControl.OnCreateControl()RadControl.OnHandleDestroyed(EventArgs)RadControl.OnVisibleChanged(EventArgs)RadControl.OnFontChanged(EventArgs)RadControl.OnForeColorChanged(EventArgs)RadControl.OnBackColorChanged(EventArgs)RadControl.OnEnabledChanged(EventArgs)RadControl.OnLocationChanged(EventArgs)RadControl.OnPaddingChanged(EventArgs)RadControl.OnPaint(PaintEventArgs)RadControl.OnLayout(LayoutEventArgs)RadControl.OnAutoSizeChanged(EventArgs)RadControl.OnInvalidated(RadElement)RadControl.OnLoad(Size)RadControl.OnCaptureLosing()RadControl.OnThemeChanged()RadControl.OnToolTipTextNeeded(object, ToolTipTextNeededEventArgs)RadControl.OnScreenTipNeeded(object, ScreenTipNeededEventArgs)RadControl.OnThemeNameChanged(ThemeNameChangedEventArgs)RadControl.ProcessMnemonic(char)RadControl.ProcessFocusRequested(RadElement)RadControl.ProcessCaptureChangeRequested(RadElement, bool)RadControl.GetInputElement()RadControl.BeginInit()RadControl.OnNotifyPropertyChanged(string)RadControl.OnNotifyPropertyChanged(PropertyChangedEventArgs)RadControl.OnZoomGesture(ZoomGestureEventArgs)RadControl.OnRotateGesture(RotateGestureEventArgs)RadControl.OnPanGesture(PanGestureEventArgs)RadControl.OnTwoFingerTapGesture(GestureEventArgs)RadControl.OnPressAndTapGesture(PressAndTapGestureEventArgs)RadControl.OnGesture(GestureEventArgs)RadControl.ProcessGesture(Message)RadControl.EnableGesture(GestureType)RadControl.DisableGesture(GestureType)RadControl.Refresh()RadControl.SuspendUpdate()RadControl.ResumeUpdate()RadControl.ResumeUpdate(bool)RadControl.InvokeLayoutCallback(LayoutCallback)RadControl.RegisterHostedControl(RadHostItem)RadControl.UnregisterHostedControl(RadHostItem, bool)RadControl.ResolveStyleGroupForElement(StyleGroup, RadObject)RadControl.GetPlainText()RadControl.ShouldSerializeProperty(RadProperty)RadControl.ShouldSerializeProperty(RadProperty, RadObject)RadControl.ResetProperty(RadProperty, RadObject)RadControl.CanEditElementAtDesignTime(RadElement)RadControl.FindPropertyInChildren(RadControl, IPCMessage)RadControl.ScaleControl(SizeF, BoundsSpecified)RadControl.PerformRadAutoScale(BoundsSpecified?)RadControl.GetMonitorDpiScaleFactor(Control)RadControl.SetRadAutoScale(bool)RadControl.EnableDpiScalingRadControl.EnableRadAutoScaleRadControl.EnableRadFormInitialDpiScalingRadControl.EnableImageDpiScalingRadControl.EnableSvgImagesRadControl.IsLoadedRadControl.ElementTreeRadControl.UseCompatibleTextRenderingDefaultValueRadControl.BehaviorRadControl.RootElementRadControl.PaddingRadControl.ThemeNameRadControl.EnableThemingRadControl.ThemeClassNameRadControl.ImageListRadControl.ImageScalingSizeRadControl.UseCompatibleTextRenderingRadControl.MaximumSizeRadControl.MinimumSizeRadControl.FocusableRadControl.SiteRadControl.IsInitializingRadControl.SmallImageListRadControl.SmallImageScalingSizeRadControl.IsDesignModeRadControl.IsDisplayedRadControl.FocusedElementRadControl.ShowItemToolTipsRadControl.CommandBindingsRadControl.EnableKeyMapRadControl.BackColorRadControl.ForeColorRadControl.ValidationCancelRadControl.EnableAnalyticsRadControl.AnalyticsNameRadControl.EnableRadAccessibilityObjectsRadControl.EnableCodedUITestsRadControl.EnableCodedUITestsDefaultValueRadControl.EnableUIAutomationDefaultValueRadControl.ElementInvalidatedRadControl.ToolTipTextNeededRadControl.ScreenTipNeededRadControl.ThemeNameChangedRadControl.InitializedRadControl.PropertyChangedRadControl.ZoomGestureRadControl.RotateGestureRadControl.PanGestureRadControl.TwoFingerTapGestureRadControl.PressAndTapGestureScrollableControl.ScrollStateAutoScrollingScrollableControl.ScrollStateHScrollVisibleScrollableControl.ScrollStateVScrollVisibleScrollableControl.ScrollStateUserHasScrolledScrollableControl.ScrollStateFullDragScrollableControl.AdjustFormScrollbars(bool)ScrollableControl.GetScrollState(int)ScrollableControl.OnPaintBackground(PaintEventArgs)ScrollableControl.SetDisplayRectLocation(int, int)ScrollableControl.ScrollControlIntoView(Control)ScrollableControl.ScrollToControl(Control)ScrollableControl.OnScroll(ScrollEventArgs)ScrollableControl.SetAutoScrollMargin(int, int)ScrollableControl.SetScrollState(int, bool)ScrollableControl.AutoScrollScrollableControl.AutoScrollMarginScrollableControl.AutoScrollPositionScrollableControl.AutoScrollMinSizeScrollableControl.CreateParamsScrollableControl.DisplayRectangleScrollableControl.HScrollScrollableControl.HorizontalScrollScrollableControl.VScrollScrollableControl.VerticalScrollScrollableControl.ScrollControl.GetAccessibilityObjectById(int)Control.SetAutoSizeMode(AutoSizeMode)Control.GetAutoSizeMode()Control.AccessibilityNotifyClients(AccessibleEvents, int)Control.AccessibilityNotifyClients(AccessibleEvents, int, int)Control.BeginInvoke(Delegate)Control.BeginInvoke(Delegate, params object[])Control.BringToFront()Control.Contains(Control)Control.CreateControlsInstance()Control.CreateGraphics()Control.CreateHandle()Control.CreateControl()Control.DefWndProc(ref Message)Control.DestroyHandle()Control.DoDragDrop(object, DragDropEffects)Control.DrawToBitmap(Bitmap, Rectangle)Control.EndInvoke(IAsyncResult)Control.FindForm()Control.GetTopLevel()Control.RaiseKeyEvent(object, KeyEventArgs)Control.RaiseMouseEvent(object, MouseEventArgs)Control.Focus()Control.FromChildHandle(IntPtr)Control.FromHandle(IntPtr)Control.GetChildAtPoint(Point, GetChildAtPointSkip)Control.GetChildAtPoint(Point)Control.GetContainerControl()Control.GetScaledBounds(Rectangle, SizeF, BoundsSpecified)Control.GetNextControl(Control, bool)Control.GetStyle(ControlStyles)Control.Hide()Control.InitLayout()Control.Invalidate(Region)Control.Invalidate(Region, bool)Control.Invalidate()Control.Invalidate(bool)Control.Invalidate(Rectangle)Control.Invalidate(Rectangle, bool)Control.Invoke(Delegate)Control.Invoke(Delegate, params object[])Control.InvokePaint(Control, PaintEventArgs)Control.InvokePaintBackground(Control, PaintEventArgs)Control.IsKeyLocked(Keys)Control.IsMnemonic(char, string)Control.LogicalToDeviceUnits(int)Control.LogicalToDeviceUnits(Size)Control.ScaleBitmapLogicalToDevice(ref Bitmap)Control.NotifyInvalidate(Rectangle)Control.InvokeOnClick(Control, EventArgs)Control.OnBackgroundImageChanged(EventArgs)Control.OnBackgroundImageLayoutChanged(EventArgs)Control.OnCausesValidationChanged(EventArgs)Control.OnContextMenuChanged(EventArgs)Control.OnContextMenuStripChanged(EventArgs)Control.OnCursorChanged(EventArgs)Control.OnDockChanged(EventArgs)Control.OnNotifyMessage(Message)Control.OnParentBackColorChanged(EventArgs)Control.OnParentBackgroundImageChanged(EventArgs)Control.OnParentBindingContextChanged(EventArgs)Control.OnParentCursorChanged(EventArgs)Control.OnParentEnabledChanged(EventArgs)Control.OnParentFontChanged(EventArgs)Control.OnParentForeColorChanged(EventArgs)Control.OnParentRightToLeftChanged(EventArgs)Control.OnParentVisibleChanged(EventArgs)Control.OnPrint(PaintEventArgs)Control.OnTabIndexChanged(EventArgs)Control.OnTabStopChanged(EventArgs)Control.OnTextChanged(EventArgs)Control.OnClientSizeChanged(EventArgs)Control.OnControlAdded(ControlEventArgs)Control.OnControlRemoved(ControlEventArgs)Control.OnHandleCreated(EventArgs)Control.OnDragEnter(DragEventArgs)Control.OnDragOver(DragEventArgs)Control.OnDragLeave(EventArgs)Control.OnDragDrop(DragEventArgs)Control.OnGiveFeedback(GiveFeedbackEventArgs)Control.InvokeGotFocus(Control, EventArgs)Control.OnHelpRequested(HelpEventArgs)Control.OnInvalidated(InvalidateEventArgs)Control.InvokeLostFocus(Control, EventArgs)Control.OnMarginChanged(EventArgs)Control.OnMouseDoubleClick(MouseEventArgs)Control.OnMouseClick(MouseEventArgs)Control.OnDpiChangedBeforeParent(EventArgs)Control.OnDpiChangedAfterParent(EventArgs)Control.OnMove(EventArgs)Control.OnQueryContinueDrag(QueryContinueDragEventArgs)Control.OnRegionChanged(EventArgs)Control.OnResize(EventArgs)Control.OnSizeChanged(EventArgs)Control.OnChangeUICues(UICuesEventArgs)Control.OnStyleChanged(EventArgs)Control.OnSystemColorsChanged(EventArgs)Control.OnValidating(CancelEventArgs)Control.OnValidated(EventArgs)Control.RescaleConstantsForDpi(int, int)Control.PerformLayout()Control.PerformLayout(Control, string)Control.PointToClient(Point)Control.PointToScreen(Point)Control.PreProcessMessage(ref Message)Control.PreProcessControlMessage(ref Message)Control.ProcessCmdKey(ref Message, Keys)Control.ProcessDialogChar(char)Control.ProcessDialogKey(Keys)Control.ProcessKeyEventArgs(ref Message)Control.ProcessKeyMessage(ref Message)Control.ProcessKeyPreview(ref Message)Control.RaiseDragEvent(object, DragEventArgs)Control.RaisePaintEvent(object, PaintEventArgs)Control.RecreateHandle()Control.RectangleToClient(Rectangle)Control.RectangleToScreen(Rectangle)Control.ReflectMessage(IntPtr, ref Message)Control.ResetMouseEventArgs()Control.ResetText()Control.ResumeLayout()Control.ResumeLayout(bool)Control.Scale(SizeF)Control.Select()Control.Select(bool, bool)Control.SelectNextControl(Control, bool, bool, bool, bool)Control.SendToBack()Control.SetBounds(int, int, int, int)Control.SetBounds(int, int, int, int, BoundsSpecified)Control.SetClientSizeCore(int, int)Control.SizeFromClientSize(Size)Control.SetStyle(ControlStyles, bool)Control.SetTopLevel(bool)Control.SetVisibleCore(bool)Control.RtlTranslateAlignment(HorizontalAlignment)Control.RtlTranslateAlignment(LeftRightAlignment)Control.RtlTranslateAlignment(ContentAlignment)Control.RtlTranslateHorizontal(HorizontalAlignment)Control.RtlTranslateLeftRight(LeftRightAlignment)Control.RtlTranslateContent(ContentAlignment)Control.Show()Control.SuspendLayout()Control.Update()Control.UpdateBounds()Control.UpdateBounds(int, int, int, int)Control.UpdateBounds(int, int, int, int, int, int)Control.UpdateZOrder()Control.UpdateStyles()Control.OnImeModeChanged(EventArgs)Control.AccessibilityObjectControl.AccessibleDefaultActionDescriptionControl.AccessibleDescriptionControl.AccessibleNameControl.AccessibleRoleControl.AllowDropControl.AnchorControl.AutoScrollOffsetControl.LayoutEngineControl.BackgroundImageControl.BackgroundImageLayoutControl.BindingContextControl.BottomControl.BoundsControl.CanFocusControl.CanRaiseEventsControl.CanSelectControl.CaptureControl.CheckForIllegalCrossThreadCallsControl.ClientRectangleControl.ClientSizeControl.CompanyNameControl.ContainsFocusControl.ContextMenuControl.ContextMenuStripControl.ControlsControl.CreatedControl.CursorControl.DataBindingsControl.DefaultBackColorControl.DefaultCursorControl.DefaultFontControl.DefaultForeColorControl.DefaultMarginControl.DefaultMaximumSizeControl.DefaultMinimumSizeControl.DefaultPaddingControl.DeviceDpiControl.IsDisposedControl.DisposingControl.DockControl.DoubleBufferedControl.EnabledControl.FocusedControl.FontHeightControl.HandleControl.HasChildrenControl.HeightControl.IsHandleCreatedControl.InvokeRequiredControl.IsAccessibleControl.IsMirroredControl.LeftControl.LocationControl.MarginControl.ModifierKeysControl.MouseButtonsControl.MousePositionControl.NameControl.ParentControl.ProductNameControl.ProductVersionControl.RecreatingHandleControl.RegionControl.RenderRightToLeftControl.ResizeRedrawControl.RightControl.RightToLeftControl.ScaleChildrenControl.SizeControl.TabIndexControl.TagControl.TopControl.TopLevelControlControl.ShowKeyboardCuesControl.ShowFocusCuesControl.UseWaitCursorControl.VisibleControl.WidthControl.PreferredSizeControl.CanEnableImeControl.DefaultImeModeControl.ImeModeControl.ImeModeBaseControl.PropagatingImeModeControl.BackColorChangedControl.BackgroundImageChangedControl.BackgroundImageLayoutChangedControl.BindingContextChangedControl.CausesValidationChangedControl.ClientSizeChangedControl.ContextMenuChangedControl.ContextMenuStripChangedControl.CursorChangedControl.DockChangedControl.EnabledChangedControl.FontChangedControl.ForeColorChangedControl.LocationChangedControl.MarginChangedControl.RegionChangedControl.RightToLeftChangedControl.SizeChangedControl.TabIndexChangedControl.TabStopChangedControl.VisibleChangedControl.ClickControl.ControlAddedControl.ControlRemovedControl.DragDropControl.DragEnterControl.DragOverControl.DragLeaveControl.GiveFeedbackControl.HandleCreatedControl.HandleDestroyedControl.HelpRequestedControl.InvalidatedControl.PaddingChangedControl.PaintControl.QueryContinueDragControl.QueryAccessibilityHelpControl.DoubleClickControl.EnterControl.GotFocusControl.LayoutControl.LeaveControl.LostFocusControl.MouseClickControl.MouseDoubleClickControl.MouseCaptureChangedControl.MouseDownControl.MouseEnterControl.MouseLeaveControl.DpiChangedBeforeParentControl.DpiChangedAfterParentControl.MouseHoverControl.MouseMoveControl.MouseUpControl.MouseWheelControl.MoveControl.PreviewKeyDownControl.ResizeControl.ChangeUICuesControl.StyleChangedControl.SystemColorsChangedControl.ValidatingControl.ValidatedControl.ParentChangedControl.ImeModeChangedComponent.Dispose()Component.GetService(Type)Component.ToString()Component.EventsComponent.ContainerComponent.DesignModeComponent.DisposedMarshalByRefObject.MemberwiseClone(bool)MarshalByRefObject.GetLifetimeService()MarshalByRefObject.InitializeLifetimeService()MarshalByRefObject.CreateObjRef(Type)

Constructors

RadDropDownList()

Initializes a new instance of the RadDropDownList class. Sets default properties such as AutoSize to true, configures the control to be selectable, and establishes property bindings between the root element and dropdown list element.

Declaration

cs-api-definition
public RadDropDownList()

Fields

CreatingVisualListItemEventKey

Declaration

cs-api-definition
public static readonly object CreatingVisualListItemEventKey

Field Value

object

KeyDownEventKey

Declaration

cs-api-definition
public static readonly object KeyDownEventKey

Field Value

object

KeyPressEventKey

Declaration

cs-api-definition
public static readonly object KeyPressEventKey

Field Value

object

KeyUpEventKey

Declaration

cs-api-definition
public static readonly object KeyUpEventKey

Field Value

object

ListItemDataBindingEventKey

Declaration

cs-api-definition
public static readonly object ListItemDataBindingEventKey

Field Value

object

ListItemDataBoundEventKey

Declaration

cs-api-definition
public static readonly object ListItemDataBoundEventKey

Field Value

object

PopupClosedEventKey

Declaration

cs-api-definition
public static readonly object PopupClosedEventKey

Field Value

object

PopupClosingEventKey

Declaration

cs-api-definition
public static readonly object PopupClosingEventKey

Field Value

object

PopupOpenedEventKey

Declaration

cs-api-definition
public static readonly object PopupOpenedEventKey

Field Value

object

PopupOpeningEventKey

Declaration

cs-api-definition
public static readonly object PopupOpeningEventKey

Field Value

object

SelectedIndexChangedEventKey

Declaration

cs-api-definition
public static readonly object SelectedIndexChangedEventKey

Field Value

object

SelectedIndexChangingEventKey

Declaration

cs-api-definition
public static readonly object SelectedIndexChangingEventKey

Field Value

object

SelectedValueChangedEventKey

Declaration

cs-api-definition
public static readonly object SelectedValueChangedEventKey

Field Value

object

SelectionRangeChangedKey

Declaration

cs-api-definition
public static readonly object SelectionRangeChangedKey

Field Value

object

SortStyleChangedKey

Declaration

cs-api-definition
public static readonly object SortStyleChangedKey

Field Value

object

VisualItemFormattingKey

Declaration

cs-api-definition
public static readonly object VisualItemFormattingKey

Field Value

object

Properties

AllowShowFocusCues

Gets or sets a value indicating whether visual focus cues are displayed when the control has input focus. Focus cues are visual indicators (like a border or highlight) that show which control is currently active, improving accessibility and keyboard navigation feedback for users.

Declaration

cs-api-definition
[Browsable(true)]
public override bool AllowShowFocusCues { get; set; }

Property Value

bool

Overrides RadControl.AllowShowFocusCues

AutoCompleteDataSource

Gets or sets the object that provides data items for the AutoComplete suggestion feature. When typing in the control with AutoComplete enabled, this data source is used to generate suggestions based on what the user is typing.

Declaration

cs-api-definition
[Browsable(false)]
public virtual object AutoCompleteDataSource { get; set; }

Property Value

object

AutoCompleteDisplayMember

Gets or sets the property name used to display text for each item in the AutoComplete suggestion list. This property specifies which field from the AutoCompleteDataSource objects should be displayed in the suggestion list. Cannot be set to null - will be converted to an empty string.

Declaration

cs-api-definition
[Browsable(false)]
[TypeConverter("System.Windows.Forms.Design.DataMemberFieldConverter, System.Design, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")]
public virtual string AutoCompleteDisplayMember { get; set; }

Property Value

string

AutoCompleteMode

Gets or sets the mode for the automatic text completion feature used in the RadDropDownList. This property determines how autocomplete behavior works: None (disabled), Suggest (shows matching items), Append (automatically completes text in the editor), or SuggestAppend (combines both behaviors). This feature assists users in quickly finding and selecting items while typing.

Declaration

cs-api-definition
[Browsable(true)]
public virtual AutoCompleteMode AutoCompleteMode { get; set; }

Property Value

AutoCompleteMode

AutoCompleteValueMember

Gets or sets the property name used to determine the value of items in the AutoComplete suggestion list. This property specifies which field from the AutoCompleteDataSource objects should be used as the underlying value when an AutoComplete suggestion is selected. Cannot be set to null - will be converted to an empty string.

Declaration

cs-api-definition
[Browsable(false)]
public virtual string AutoCompleteValueMember { get; set; }

Property Value

string

AutoSize

Gets or sets a value indicating whether the RadDropDownList control automatically adjusts its size. When enabled, the control will resize itself to properly display its content and selected item, ensuring that text is not cut off and visual elements are properly aligned.

Declaration

cs-api-definition
[Browsable(true)]
public override bool AutoSize { get; set; }

Property Value

bool

Overrides RadControl.AutoSize

AutoSizeItems

Gets or sets a value that indicates whether items will be sized according to their content. When enabled, each item will automatically adjust its height based on its text, image, and other content. For fine-grained control, you can set the Height property of individual RadListDataItem objects in the Items collection to override the automatic sizing behavior for specific items.

Declaration

cs-api-definition
[Browsable(true)]
public virtual bool AutoSizeItems { get; set; }

Property Value

bool

CaseSensitive

Gets or sets a value indicating whether string comparisons are case-sensitive. When enabled, searching, filtering, and item selection operations will match the exact letter case, distinguishing between uppercase and lowercase letters. This affects text matching operations such as finding items during typing or when filtering the dropdown list.

Declaration

cs-api-definition
[Browsable(true)]
public virtual bool CaseSensitive { get; set; }

Property Value

bool

CausesValidation

Gets or sets a value indicating whether the control causes validation to be performed on any controls that require validation when it receives focus. When set to true, this property ensures that validation rules are applied to other controls on the form before the focus moves to this control.

Declaration

cs-api-definition
public bool CausesValidation { get; set; }

Property Value

bool

true if the control causes validation to be performed on any controls requiring validation when it receives focus; otherwise, false. The default value is true.

DataMember

Gets or sets the name of the specific list or table within the data source that the RadDropDownList should display. This is particularly useful when the data source contains multiple tables or lists and you need to specify which one to use.

Declaration

cs-api-definition
[Browsable(true)]
public string DataMember { get; set; }

Property Value

string

DataSource

Gets or sets the data source for the RadDropDownList control. The data source can be any object that implements the IList or IListSource interface, such as a DataTable or an array of objects.

Declaration

cs-api-definition
public object DataSource { get; set; }

Property Value

object

DefaultItemsCountInDropDown

Gets or sets the default number of items displayed in the drop-down portion of the RadDropDownList before scrolling is required. This value is used to calculate the default dropdown height when no explicit height is specified.

Declaration

cs-api-definition
[Browsable(true)]
public virtual int DefaultItemsCountInDropDown { get; set; }

Property Value

int

DefaultSize

Gets the default size of the RadDropDownList control when it is first created. This defines the initial dimensions before any auto-sizing or manual resizing occurs.

Declaration

cs-api-definition
protected override Size DefaultSize { get; }

Property Value

Size

A Size object representing the default size of the control (125x20 pixels).

Overrides Control.DefaultSize

DescriptionTextMember

Gets or sets the property name used to extract descriptive text from data source items. When the control is bound to a data source, this property specifies which field provides additional descriptive text for each item. This text is accessible via the Value property of each RadListDataItem in the Items collection.

Declaration

cs-api-definition
[Browsable(true)]
public string DescriptionTextMember { get; set; }

Property Value

string

DisplayMember

Gets or sets the property name used to display text for each item in the dropdown list. When the control is bound to a data source, this property specifies which field from the data source objects should be displayed as text in the list items. Cannot be set to null - will be converted to an empty string.

Declaration

cs-api-definition
[TypeConverter("System.Windows.Forms.Design.DataMemberFieldConverter, System.Design, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")]
public string DisplayMember { get; set; }

Property Value

string

DropDownAnimationEasing

Gets or sets the easing type for the dropdown animation. The easing type controls the rate of change of the animation over time, creating effects like acceleration, deceleration, bouncing, etc. This property only has an effect when DropDownAnimationEnabled is true.

Declaration

cs-api-definition
[Browsable(true)]
public virtual RadEasingType DropDownAnimationEasing { get; set; }

Property Value

RadEasingType

DropDownAnimationEnabled

Gets or sets a value indicating whether the dropdown portion of the control will use animation effects when opening and closing. When enabled, the dropdown slides into view with a smooth transition effect rather than appearing instantly.

Declaration

cs-api-definition
public virtual bool DropDownAnimationEnabled { get; set; }

Property Value

bool

DropDownAnimationFrames

Gets or sets the number of frames that will be used when the dropdown is being animated. Higher frame counts result in smoother animations but may require more processing power. This property only has an effect when DropDownAnimationEnabled is true.

Declaration

cs-api-definition
public virtual int DropDownAnimationFrames { get; set; }

Property Value

int

DropDownHeight

Gets or sets the height in pixels of the drop-down portion of the RadDropDownList. This controls the vertical size of the popup that displays the list items when the dropdown is activated. If there are more items than can fit in the specified height, a scrollbar appears.

Declaration

cs-api-definition
public virtual int DropDownHeight { get; set; }

Property Value

int

DropDownListElement

Gets the core RadDropDownListElement that implements the functionality of this control. This element manages the dropdown behavior, item display, and selection operations.

Declaration

cs-api-definition
[Browsable(true)]
public virtual RadDropDownListElement DropDownListElement { get; }

Property Value

RadDropDownListElement

DropDownMaxSize

Gets or sets the maximum size of the drop-down portion of the RadDropDownList. This defines the largest dimensions the dropdown can have, even when resizable or when containing many items. This helps ensure the dropdown remains manageable on screen.

Declaration

cs-api-definition
public virtual Size DropDownMaxSize { get; set; }

Property Value

Size

DropDownMinSize

Gets or sets the minimum size of the drop-down portion of the RadDropDownList control. This defines the smallest dimensions the dropdown can have, regardless of content or the number of items. Setting a larger minimum size can improve usability by ensuring the dropdown is always large enough to be easily interacted with.

Declaration

cs-api-definition
[Browsable(true)]
public virtual Size DropDownMinSize { get; set; }

Property Value

Size

DropDownSizingMode

Gets or sets a value from the SizingMode enumeration that determines how the drop-down popup can be resized by the user. Options include vertical resizing, horizontal resizing, resizing in both directions, or no resizing at all. When enabled, this allows users to dynamically adjust the size of the dropdown to see more items or view longer item content.

Declaration

cs-api-definition
[Browsable(true)]
public virtual SizingMode DropDownSizingMode { get; set; }

Property Value

SizingMode

DropDownStyle

Gets or sets a value specifying the style of the RadDropDownList. This determines how the control behaves: DropDown style allows direct text editing, while DropDownList style only permits selection from the dropdown list.

Declaration

cs-api-definition
public virtual RadDropDownStyle DropDownStyle { get; set; }

Property Value

RadDropDownStyle

EnableAlternatingItemColor

Gets or sets a value indicating whether alternating item color is enabled. When enabled, list items will be displayed with alternating background colors for better visual distinction between adjacent items in the dropdown list.

Declaration

cs-api-definition
[Browsable(true)]
public virtual bool EnableAlternatingItemColor { get; set; }

Property Value

bool

EnableKineticScrolling

Gets or sets a value indicating whether the kinetic scrolling function is enabled. When enabled, the dropdown list will support momentum-based scrolling, providing a more natural touch-friendly experience where scrolling continues briefly after the user releases their touch gesture, simulating physical inertia.

Declaration

cs-api-definition
[Browsable(true)]
public virtual bool EnableKineticScrolling { get; set; }

Property Value

bool

EnableMouseWheel

Gets or sets a value indicating whether mouse wheel scrolling is enabled. When enabled, users can navigate through the dropdown list items by rotating the mouse wheel, changing the selected item without having to click directly on items.

Declaration

cs-api-definition
public bool EnableMouseWheel { get; set; }

Property Value

bool

EnableUIAutomation

Gets or sets a value indicating whether UI Automation support is enabled for this control. When enabled, the control provides accessibility information to assistive technologies.

Declaration

cs-api-definition
public override bool EnableUIAutomation { get; set; }

Property Value

bool

Overrides RadControl.EnableUIAutomation

Implements ISupportRootUIAutomation.EnableUIAutomation

Filter

Gets or sets a predicate function that determines which RadListDataItem objects should be visible in the dropdown list. Items for which the predicate returns true will be displayed, while items for which it returns false will be hidden. This provides programmatic filtering capability.

Declaration

cs-api-definition
[Browsable(false)]
public Predicate<RadListDataItem> Filter { get; set; }

Property Value

Predicate<RadListDataItem>

FilterExpression

Gets or sets a string expression that determines which items will be visible in the dropdown list. The filter expression is a string-based alternative to the Filter predicate, allowing filtering to be specified declaratively in design-time properties or through data binding.

Declaration

cs-api-definition
[Browsable(true)]
public string FilterExpression { get; set; }

Property Value

string

FindStringComparer

Gets or sets an object that implements IFindStringComparer interface. This property provides custom string comparison functionality used by the FindString methods when searching for items in the drop-down list. It allows you to implement custom search logic such as case-insensitive or culture-specific comparisons.

Declaration

cs-api-definition
[Browsable(false)]
public IFindStringComparer FindStringComparer { get; set; }

Property Value

IFindStringComparer

FitItemsToSize

Gets or sets a value indicating whether items should be resized to fit the available width in the drop-down list. When enabled, items will automatically adjust their width to match the width of the dropdown area, preventing horizontal scrolling and ensuring all content fits within the visible area.

Declaration

cs-api-definition
public virtual bool FitItemsToSize { get; set; }

Property Value

bool

Font

Gets or sets the font used for text display in the control. This property affects the font of the root element. Setting this property to null resets the font to the default value defined in the currently applied theme. This provides consistent typography styling across themed controls.

Declaration

cs-api-definition
public override Font Font { get; set; }

Property Value

Font

Overrides RadControl.Font

FormatInfo

Gets or sets an object that implements the IFormatProvider interface. This object is used when formatting items displayed in the dropdown list. The default provider is CultureInfo.CurrentCulture, which formats items according to the current system locale settings.

Declaration

cs-api-definition
[Browsable(false)]
public virtual IFormatProvider FormatInfo { get; set; }

Property Value

IFormatProvider

FormatString

Gets or sets a format string that will be used for visual item formatting if FormattingEnabled is set to true. The format string follows the .NET formatting syntax (like "{0:C}") and applies to the display value of each item, allowing for custom formatting of numeric values, dates, or other data types.

Declaration

cs-api-definition
public virtual string FormatString { get; set; }

Property Value

string

FormattingEnabled

Gets or sets a value that determines whether text formatting is enabled for the visual items. When enabled, the control applies the format specified by FormatString to the display values, allowing for custom formatting such as currency symbols, date formats, or numeric precision.

Declaration

cs-api-definition
public virtual bool FormattingEnabled { get; set; }

Property Value

bool

IsFilterActive

Gets a value indicating whether there is either a Filter predicate or a FilterExpression string currently set and active. This property helps determine if the items in the dropdown are being filtered by any mechanism.

Declaration

cs-api-definition
[Browsable(false)]
public bool IsFilterActive { get; }

Property Value

bool

IsPopupVisible

Gets a value indicating whether the dropdown popup portion of the control is currently visible. This read-only property can be used to determine if the dropdown list is open or closed.

Declaration

cs-api-definition
[Browsable(false)]
public virtual bool IsPopupVisible { get; }

Property Value

bool

ItemHeight

Gets or sets the height in pixels for all items in the dropdown list. This property determines the uniform height of each item in the list, affecting the overall appearance and spacing. Note that this property is ignored when AutoSizeItems is set to true.

Declaration

cs-api-definition
[Browsable(true)]
public int ItemHeight { get; set; }

Property Value

int

Items

Gets the collection of RadListDataItem objects that represent the items displayed in this dropdown list. This collection can be modified directly to add, remove, or modify items in the dropdown.

Declaration

cs-api-definition
public virtual RadListDataItemCollection Items { get; }

Property Value

RadListDataItemCollection

ItemsSortComparer

Gets or sets an object that implements IComparer<T> which is used when sorting items. This property allows you to define a custom sorting algorithm for the items displayed in the drop-down list, providing greater flexibility than the default alphabetical sorting.

Declaration

cs-api-definition
[Browsable(false)]
public IComparer<RadListDataItem> ItemsSortComparer { get; set; }

Property Value

IComparer<RadListDataItem>

ListElement

Gets or sets the RadListElement that manages the list portion of this dropdown control. This element is responsible for displaying, arranging, and managing the list items in the dropdown.

Declaration

cs-api-definition
[Browsable(false)]
public RadListElement ListElement { get; set; }

Property Value

RadListElement

MaxDropDownItems

Gets or sets the maximum number of items to be shown in the drop-down portion of the RadDropDownList without requiring scrolling. A value of 0 means that all items will be shown without a scrollbar if space permits; otherwise, the dropdown will display the specified number of items and provide scrolling for additional items.

Declaration

cs-api-definition
public virtual int MaxDropDownItems { get; set; }

Property Value

int

MaxLength

Gets or sets the maximum number of characters the user can type or paste into the text box portion of the RadDropDownList control. This property primarily affects the control when using DropDown style, as it limits the length of text that can be manually entered. Has no effect when the control is in DropDownList mode.

Declaration

cs-api-definition
public virtual int MaxLength { get; set; }

Property Value

int

NullText

Gets or sets the text that is displayed when RadDropDownList has no text set. This placeholder text appears in a grayed-out font when the control has focus but no value has been entered or selected, providing users with guidance on what to enter or select.

Declaration

cs-api-definition
public string NullText { get; set; }

Property Value

string

Popup

Gets a reference to the drop-down popup form associated with this RadDropDownList. This property provides access to the actual popup control, allowing you to customize its appearance, behavior, and content at runtime or during design.

Declaration

cs-api-definition
[Browsable(false)]
public virtual RadEditorPopupControlBase Popup { get; }

Property Value

RadEditorPopupControlBase

ReadOnly

Gets or sets a value indicating whether the dropdown list is read-only. When set to true, users can view the content but cannot change the selection or edit the text in the control. This is useful for display-only scenarios where user interaction should be prevented.

Declaration

cs-api-definition
[Browsable(true)]
public virtual bool ReadOnly { get; set; }

Property Value

bool

SelectNextOnDoubleClick

Gets or sets a value indicating whether the control should automatically select the next item when the user double-clicks in the edit box area. When enabled, this feature allows users to cycle through available options without opening the dropdown, providing a quick way to browse through sequential items in the list.

Declaration

cs-api-definition
[Browsable(true)]
public virtual bool SelectNextOnDoubleClick { get; set; }

Property Value

bool

SelectedIndex

Gets or sets the zero-based index of the currently selected item in the dropdown list. A value of -1 indicates that no item is selected. Setting this property will cause the SelectedIndexChanging and SelectedIndexChanged events to fire and will update the displayed text to match the newly selected item.

Declaration

cs-api-definition
[Browsable(false)]
[Bindable(true)]
public virtual int SelectedIndex { get; set; }

Property Value

int

SelectedItem

Gets or sets the currently selected RadListDataItem in the dropdown list. This is the actual item object rather than just its value or index. Setting this property will trigger the selection changed events and update the displayed text.

Declaration

cs-api-definition
[Browsable(false)]
[Bindable(true)]
public virtual RadListDataItem SelectedItem { get; set; }

Property Value

RadListDataItem

SelectedItems

Provides a read-only collection of the currently selected items in the dropdown list. While the RadDropDownList typically allows only single selection, this property maintains interface compatibility with other list controls.

Declaration

cs-api-definition
public IReadOnlyCollection<RadListDataItem> SelectedItems { get; }

Property Value

IReadOnlyCollection<RadListDataItem>

SelectedText

Gets or sets the text that is currently selected in the editable portion of the DropDownList. This property is only applicable when the control has an editable text portion. Setting this property replaces the selected text with the specified value.

Declaration

cs-api-definition
[Browsable(false)]
public string SelectedText { get; set; }

Property Value

string

SelectedValue

Gets or sets the value of the currently selected item in the dropdown list. This corresponds to the value of the property specified by ValueMember. Setting this property to a value that is shared by multiple items will select the first matching item. Setting this property will trigger the selection changed events.

Declaration

cs-api-definition
[Browsable(false)]
[Bindable(true)]
public virtual object SelectedValue { get; set; }

Property Value

object

SelectionLength

Gets or sets the number of characters selected in the editable portion of the drop-down list. This property allows you to determine or control the length of the current text selection. A value of 0 indicates that no text is selected (the caret is positioned without selection).

Declaration

cs-api-definition
[Browsable(false)]
public int SelectionLength { get; set; }

Property Value

int

SelectionStart

Gets or sets the starting character position of the current text selection in the editable portion of the drop-down list. The index is zero-based, meaning the first character position is 0, not 1. This property is only applicable when the control has an editable text portion.

Declaration

cs-api-definition
[Browsable(false)]
public int SelectionStart { get; set; }

Property Value

int

ShowImageInEditorArea

Gets or sets a value indicating whether the RadListDataItem image will be displayed in the editor element when DropDownStyle is set to DropDownList. When enabled, images associated with list items will be shown alongside text in the main control area.

Declaration

cs-api-definition
public virtual bool ShowImageInEditorArea { get; set; }

Property Value

bool

SortStyle

Gets or sets the sort style for items in the dropdown list. It can be Ascending, Descending, or None. When sorting is enabled, items are ordered based on the property specified by DisplayMember. This affects how items appear in the dropdown portion of the control.

Declaration

cs-api-definition
public virtual SortStyle SortStyle { get; set; }

Property Value

SortStyle

TabStop

Gets or sets a value indicating whether the user can give the focus to this control using the TAB key. The behavior varies based on the current DropDownStyle: when set to DropDownList, the focus applies to the text box element, otherwise it applies to the control itself.

Declaration

cs-api-definition
[Browsable(false)]
public bool TabStop { get; set; }

Property Value

bool

true if the user can give the focus to the control using the TAB key; otherwise, false.

Text

Gets or sets the text associated with this control. The text represents the content displayed in the editable portion of the drop-down list control.

Declaration

cs-api-definition
[Browsable(true)]
[Bindable(true)]
[SettingsBindable(true)]
public override string Text { get; set; }

Property Value

string

Overrides RadControl.Text

UIAutomationProvider

Gets the UI Automation Provider that exposes this control to UI Automation clients. This property is used by accessibility technologies to interact with the control.

Declaration

cs-api-definition
public IRadRawElementProviderFragmentRoot UIAutomationProvider { get; }

Property Value

IRadRawElementProviderFragmentRoot

Implements ISupportRootUIAutomation.UIAutomationProvider

ValueMember

Gets or sets the property name used to determine the underlying value of each item in the dropdown list. When the control is bound to a data source, this property specifies which field from the data source should be used as the value when an item is selected. This value is accessible through the SelectedValue property. Cannot be set to null - will be converted to an empty string.

Declaration

cs-api-definition
public string ValueMember { get; set; }

Property Value

string

Methods

BeginUpdate()

Suspends visual updates of the control. Call this method before making multiple changes to the control to prevent flickering and improve performance. Each call to BeginUpdate must be paired with a corresponding call to EndUpdate.

Declaration

cs-api-definition
public virtual void BeginUpdate()

CloseDropDown()

Programmatically hides the drop-down popup if it is currently displayed on the screen. This method allows you to close the list programmatically without user interaction, which is useful in scenarios where you need to dismiss the popup based on custom logic.

Declaration

cs-api-definition
public virtual void CloseDropDown()

ControlDefinesThemeForElement(RadElement)

Checks whether the element's theme is defined by the control.

Declaration

cs-api-definition
public override bool ControlDefinesThemeForElement(RadElement element)

Parameters

element

RadElement

The element to should be checked.

Returns

bool

true if the control defines theme for this element, false otherwise.

Overrides RadControl.ControlDefinesThemeForElement(RadElement)

Remarks

If true is returned the ThemeResolutionService would not not set any theme to the element to avoid duplicating the style settings of the element.

CreateAccessibilityInstance()

Creates and returns an accessibility object for this control. This method is used by accessibility technologies like screen readers to interact with the control.

Declaration

cs-api-definition
protected override AccessibleObject CreateAccessibilityInstance()

Returns

AccessibleObject

An AccessibleObject representing this control for accessibility purposes.

Overrides Control.CreateAccessibilityInstance()

CreateChildItems(RadElement)

Creates and initializes the child elements of the RadDropDownList control. This method creates a new RadDropDownListElement, adds it to the control's element hierarchy, and wires up the necessary events.

Declaration

cs-api-definition
protected override void CreateChildItems(RadElement parent)

Parameters

parent

RadElement

The parent element that will contain the child items.

Overrides RadControl.CreateChildItems(RadElement)

CreateDropDownListElement()

Creates a new instance of the RadDropDownListElement class that will be used as the core element of this dropdown list control. Override this method in derived classes to provide custom dropdown element implementations.

Declaration

cs-api-definition
protected virtual RadDropDownListElement CreateDropDownListElement()

Returns

RadDropDownListElement

A new instance of the RadDropDownListElement class.

CreateRootElement()

Declaration

cs-api-definition
protected override RootRadElement CreateRootElement()

Returns

RootRadElement

Overrides RadControl.CreateRootElement()

DeferRefresh()

Defers the visual refresh of the control until the returned IDisposable object is disposed. This method provides a convenient way to use the using statement to temporarily suspend updates during a block of code that makes multiple changes to the control.

Declaration

cs-api-definition
public virtual IDisposable DeferRefresh()

Returns

IDisposable

An IDisposable object that, when disposed, will resume visual updates and refresh the control.

Dispose(bool)

Releases the resources used by the RadDropDownList control.

Declaration

cs-api-definition
protected override void Dispose(bool disposing)

Parameters

disposing

bool

true to release both managed and unmanaged resources; false to release only unmanaged resources.

Overrides RadControl.Dispose(bool)

EndInit()

Resumes layout operations after initialization of the RadDropDownList is complete. Applies the binding context to ensure proper data binding between the control and its data source.

Declaration

cs-api-definition
public override void EndInit()

Overrides RadControl.EndInit()

EndUpdate()

Resumes visual updates of the control after a call to BeginUpdate. Call this method after completing multiple changes to the control to resume visual updates and apply all pending changes at once. Each call to EndUpdate must be preceded by a corresponding call to BeginUpdate.

Declaration

cs-api-definition
public virtual void EndUpdate()

FindItemExact(string, bool)

Searches for an item in the list that exactly matches the specified text.

Declaration

cs-api-definition
public RadListDataItem FindItemExact(string text, bool caseSensitive)

Parameters

text

string

The text to search for in the list items.

caseSensitive

bool

A value indicating whether the search should be case-sensitive.

Returns

RadListDataItem

The RadListDataItem that exactly matches the specified text, or null if no match is found.

FindString(string)

Searches for an item in the list that matches the specified string according to the current FindStringComparer. By default, the FindStringComparer uses the System.String.StartsWith() method for string comparison. This method starts searching from index 0, and if it reaches the end of the Items collection, it wraps to the beginning and continues until it has searched the entire collection.

Declaration

cs-api-definition
public int FindString(string s)

Parameters

s

string

The string to search for in the list items.

Returns

int

The zero-based index of the first matching item, or -1 if no match is found.

FindString(string, int)

Searches for an item in the list that matches the specified string according to the current FindStringComparer. By default, the FindStringComparer uses the System.String.StartsWith() method for string comparison. This method starts searching from the specified index, and if it reaches the end of the Items collection, it wraps to the beginning and continues until it reaches one position before the starting index.

Declaration

cs-api-definition
public int FindString(string s, int startIndex)

Parameters

s

string

The string to search for in the list items.

startIndex

int

The zero-based index at which to start the search.

Returns

int

The zero-based index of the first matching item, or -1 if no match is found.

FindStringExact(string)

Searches for an item in the list that exactly matches the specified string. Unlike FindString, this method requires an exact match rather than a partial match. The search starts from index 0 and searches the entire list.

Declaration

cs-api-definition
public int FindStringExact(string s)

Parameters

s

string

The string to search for in the list items.

Returns

int

The zero-based index of the first exactly matching item, or -1 if no exact match is found.

FindStringExact(string, int)

Searches for an item in the list that exactly matches the specified string. Unlike FindString, this method requires an exact match rather than a partial match. This method starts searching from the specified index, and if it reaches the end of the Items collection, it wraps to the beginning and continues until it reaches one position before the starting index.

Declaration

cs-api-definition
public int FindStringExact(string s, int startIndex)

Parameters

s

string

The string to search for in the list items.

startIndex

int

The zero-based index at which to start the search.

Returns

int

The zero-based index of the first exactly matching item, or -1 if no exact match is found.

FindStringNonWrapping(string)

Searches for an item in the list that matches the specified string according to the current FindStringComparer, but unlike FindString, it does not wrap around to the beginning when the end of the list is reached. The search starts from index 0 and continues until the end of the list.

Declaration

cs-api-definition
public int FindStringNonWrapping(string s)

Parameters

s

string

The string to search for in the list items.

Returns

int

The zero-based index of the first matching item, or -1 if no match is found.

FindStringNonWrapping(string, int)

Searches for an item in the list that matches the specified string according to the current FindStringComparer, but unlike FindString, it does not wrap around to the beginning when the end of the list is reached. The search starts from the specified index and continues until the end of the list.

Declaration

cs-api-definition
public int FindStringNonWrapping(string s, int startIndex)

Parameters

s

string

The string to search for in the list items.

startIndex

int

The zero-based index at which to start the search.

Returns

int

The zero-based index of the first matching item, or -1 if no match is found.

IsInputChar(char)

Declaration

cs-api-definition
protected override bool IsInputChar(char charCode)

Parameters

charCode

char

Returns

bool

Overrides Control.IsInputChar(char)

IsInputKey(Keys)

Declaration

cs-api-definition
protected override bool IsInputKey(Keys keyData)

Parameters

keyData

Keys

Returns

bool

Overrides RadControl.IsInputKey(Keys)

OnBindingContextChanged(EventArgs)

Declaration

cs-api-definition
protected override void OnBindingContextChanged(EventArgs e)

Parameters

e

EventArgs

Overrides RadControl.OnBindingContextChanged(EventArgs)

OnCreatingVisualItem(object, CreatingVisualListItemEventArgs)

Declaration

cs-api-definition
protected virtual void OnCreatingVisualItem(object sender, CreatingVisualListItemEventArgs args)

Parameters

sender

object

args

CreatingVisualListItemEventArgs

OnDataBindingComplete(object, ListBindingCompleteEventArgs)

Raises the DataBindingComplete event. This method is called after a data binding operation completes, allowing derived classes to handle this event without attaching a delegate.

Declaration

cs-api-definition
protected virtual void OnDataBindingComplete(object sender, ListBindingCompleteEventArgs e)

Parameters

sender

object

The source of the event.

e

ListBindingCompleteEventArgs

An ListBindingCompleteEventArgs instance that contains information about the binding operation.

OnEnter(EventArgs)

Raises the Enter event.

Declaration

cs-api-definition
protected override void OnEnter(EventArgs e)

Parameters

e

EventArgs

An EventArgs that contains the event data.

Overrides Control.OnEnter(EventArgs)

OnGotFocus(EventArgs)

Raises the GotFocus event.

Declaration

cs-api-definition
protected override void OnGotFocus(EventArgs e)

Parameters

e

EventArgs

An EventArgs that contains the event data.

Overrides RadControl.OnGotFocus(EventArgs)

OnItemDataBinding(object, ListItemDataBindingEventArgs)

Raises the ItemDataBinding event.

Declaration

cs-api-definition
protected virtual void OnItemDataBinding(object sender, ListItemDataBindingEventArgs args)

Parameters

sender

object

The source of the event.

args

ListItemDataBindingEventArgs

A ListItemDataBindingEventArgs that contains the event data.

OnItemDataBound(object, ListItemDataBoundEventArgs)

Raises the ItemDataBound event.

Declaration

cs-api-definition
protected virtual void OnItemDataBound(object sender, ListItemDataBoundEventArgs args)

Parameters

sender

object

The source of the event.

args

ListItemDataBoundEventArgs

A ListItemDataBoundEventArgs that contains the event data.

OnLeave(EventArgs)

Raises the Leave event.

Declaration

cs-api-definition
protected override void OnLeave(EventArgs e)

Parameters

e

EventArgs

An EventArgs that contains the event data.

Overrides Control.OnLeave(EventArgs)

OnLostFocus(EventArgs)

Raises the LostFocus event.

Declaration

cs-api-definition
protected override void OnLostFocus(EventArgs e)

Parameters

e

EventArgs

An EventArgs that contains the event data.

Overrides RadControl.OnLostFocus(EventArgs)

OnRightToLeftChanged(EventArgs)

Raises the RightToLeftChanged event. This method is called when the RightToLeft property value changes, allowing the control to update its appearance and layout for right-to-left languages.

Declaration

cs-api-definition
protected override void OnRightToLeftChanged(EventArgs e)

Parameters

e

EventArgs

An EventArgs that contains the event data.

Overrides RadControl.OnRightToLeftChanged(EventArgs)

OnSelectedIndexChanged(object, int)

Declaration

cs-api-definition
protected virtual void OnSelectedIndexChanged(object sender, int newIndex)

Parameters

sender

object

newIndex

int

OnSelectedIndexChanging(object, int)

Declaration

cs-api-definition
protected virtual bool OnSelectedIndexChanging(object sender, int newIndex)

Parameters

sender

object

newIndex

int

Returns

bool

OnSelectedValueChanged(object, int, object, object)

Declaration

cs-api-definition
protected virtual void OnSelectedValueChanged(object sender, int newIndex, object oldValue, object newValue)

Parameters

sender

object

newIndex

int

oldValue

object

newValue

object

OnSortStyleChanged(SortStyle)

Raises the SortStyleChanged event.

Declaration

cs-api-definition
protected virtual void OnSortStyleChanged(SortStyle sortStyle)

Parameters

sortStyle

SortStyle

The new sort style that was applied to the dropdown list.

OnVisualItemFormatting(RadListVisualItem)

Raises the VisualItemFormatting event.

Declaration

cs-api-definition
protected virtual void OnVisualItemFormatting(RadListVisualItem item)

Parameters

item

RadListVisualItem

The RadListVisualItem being formatted.

ProcessAutoSizeChanged(bool)

Declaration

cs-api-definition
protected override void ProcessAutoSizeChanged(bool value)

Parameters

value

bool

Overrides RadControl.ProcessAutoSizeChanged(bool)

ProcessCodedUIMessage(ref IPCMessage)

Declaration

cs-api-definition
protected override void ProcessCodedUIMessage(ref IPCMessage request)

Parameters

request

IPCMessage

Overrides RadControl.ProcessCodedUIMessage(ref IPCMessage)

Rebind()

Forces a re-evaluation and refresh of the current data source. This method is useful when the underlying data in the data source has changed and you need the control to reflect these changes without explicitly reassigning the DataSource property.

Declaration

cs-api-definition
public void Rebind()

ResetBackColorThemeOverrides()

Declaration

cs-api-definition
protected override void ResetBackColorThemeOverrides()

Overrides RadControl.ResetBackColorThemeOverrides()

ResetForeColorThemeOverrides()

Declaration

cs-api-definition
protected override void ResetForeColorThemeOverrides()

Overrides RadControl.ResetForeColorThemeOverrides()

SelectAll()

Selects all items in the drop-down list if the SelectionMode property allows multiple selection. This method can be used to quickly select all available options in the list when working with multi-select drop-down lists.

Declaration

cs-api-definition
public void SelectAll()

Exceptions

InvalidOperationException

Thrown when attempting to select all items in a selection mode that doesn't support multiple selection.

SelectAllText()

Selects all the text in the editable portion of the RadDropDownList. This is only applicable when DropDownStyle is set to DropDown. This method provides a convenient way to select the entire text content for quick editing or replacement.

Declaration

cs-api-definition
public void SelectAllText()

SelectText(int, int)

Selects a range of text in the editable portion of the RadDropDownList. This is only applicable when DropDownStyle is set to DropDown. Use this method to programmatically select text in the control for operations like cut, copy, or deletion.

Declaration

cs-api-definition
public void SelectText(int start, int length)

Parameters

start

int

The position of the first character to be selected within the text box (zero-based index).

length

int

The number of characters to select.

SetBackColorThemeOverrides()

Declaration

cs-api-definition
protected override void SetBackColorThemeOverrides()

Overrides RadControl.SetBackColorThemeOverrides()

SetForeColorThemeOverrides()

Declaration

cs-api-definition
protected override void SetForeColorThemeOverrides()

Overrides RadControl.SetForeColorThemeOverrides()

ShowDropDown()

Programmatically displays the drop-down popup on the screen, showing the list of available items. This method is equivalent to clicking the drop-down button with the mouse. It allows you to open the list programmatically without user interaction.

Declaration

cs-api-definition
public virtual void ShowDropDown()

WndProc(ref Message)

Declaration

cs-api-definition
protected override void WndProc(ref Message m)

Parameters

m

Message

Overrides RadControl.WndProc(ref Message)

dropDownListElement_KeyDown(object, KeyEventArgs)

Handles the key down event of the dropdown list element.

Declaration

cs-api-definition
protected virtual void dropDownListElement_KeyDown(object sender, KeyEventArgs e)

Parameters

sender

object

The source of the event.

e

KeyEventArgs

The key event data.

dropDownListElement_KeyPress(object, KeyPressEventArgs)

Handles the key press event of the dropdown list element.

Declaration

cs-api-definition
protected virtual void dropDownListElement_KeyPress(object sender, KeyPressEventArgs e)

Parameters

sender

object

The source of the event.

e

KeyPressEventArgs

The key press event data.

dropDownListElement_KeyUp(object, KeyEventArgs)

Handles the key up event of the dropdown list element.

Declaration

cs-api-definition
protected virtual void dropDownListElement_KeyUp(object sender, KeyEventArgs e)

Parameters

sender

object

The source of the event.

e

KeyEventArgs

The key event data.

element_PopupClosed(object, RadPopupClosedEventArgs)

Handles the popup closed event of the dropdown list element.

Declaration

cs-api-definition
protected virtual void element_PopupClosed(object sender, RadPopupClosedEventArgs args)

Parameters

sender

object

The source of the event.

args

RadPopupClosedEventArgs

The popup closed event data.

element_PopupClosing(object, RadPopupClosingEventArgs)

Handles the popup closing event of the dropdown list element.

Declaration

cs-api-definition
protected virtual void element_PopupClosing(object sender, RadPopupClosingEventArgs args)

Parameters

sender

object

The source of the event.

args

RadPopupClosingEventArgs

The popup closing event data.

element_PopupOpened(object, EventArgs)

Handles the popup opened event of the dropdown list element.

Declaration

cs-api-definition
protected virtual void element_PopupOpened(object sender, EventArgs e)

Parameters

sender

object

The source of the event.

e

EventArgs

The event data.

element_PopupOpening(object, CancelEventArgs)

Handles the popup opening event of the dropdown list element.

Declaration

cs-api-definition
protected virtual void element_PopupOpening(object sender, CancelEventArgs e)

Parameters

sender

object

The source of the event.

e

CancelEventArgs

The event data that allows cancellation of the opening.

Events

CreatingVisualListItem

Occurs when the control needs to create visual items to represent data items in the view. This event provides the opportunity to create custom visual representations of list items, allowing for advanced visual customization beyond the standard appearance. The event fires both during initial rendering and when the control is resized.

Declaration

cs-api-definition
public event CreatingVisualListItemEventHandler CreatingVisualListItem

Event Value

CreatingVisualListItemEventHandler

DataBindingComplete

Occurs when a data binding operation on the control has been completed. This event provides an opportunity to perform additional processing after items have been loaded from the data source, such as selecting a default item or performing custom filtering.

Declaration

cs-api-definition
[Browsable(true)]
public event ListBindingCompleteEventHandler DataBindingComplete

Event Value

ListBindingCompleteEventHandler

ItemDataBinding

Occurs before each RadListDataItem is bound to a data item from the data source. This event is raised once for each item in the data source during the data binding process, allowing you to customize how each item is created and initialized before it appears in the list. You can provide your own custom RadListDataItem implementation through the event arguments.

Declaration

cs-api-definition
public event ListItemDataBindingEventHandler ItemDataBinding

Event Value

ListItemDataBindingEventHandler

ItemDataBound

Occurs after each RadListDataItem has been bound to a data item from the data source. This event is raised once for each item in the data source after the initial binding process is complete, allowing you to perform additional customization or formatting of the list item based on the bound data.

Declaration

cs-api-definition
public event ListItemDataBoundEventHandler ItemDataBound

Event Value

ListItemDataBoundEventHandler

KeyDown

Occurs when a key is pressed while the control has focus. This event is raised before the KeyPress event and can be used to detect and handle special keys such as function keys, arrow keys, and other non-character keys.

Declaration

cs-api-definition
public event KeyEventHandler KeyDown

Event Value

KeyEventHandler

KeyPress

Occurs when a character key is pressed while the control has focus. This event can be used to intercept and handle specific character inputs before they are processed by the control, enabling custom input validation or special key handling.

Declaration

cs-api-definition
public event KeyPressEventHandler KeyPress

Event Value

KeyPressEventHandler

KeyUp

Occurs when a key is released while the control has focus. This event is useful for detecting when the user releases a keyboard key, which can be used for implementing custom keyboard navigation or shortcuts.

Declaration

cs-api-definition
public event KeyEventHandler KeyUp

Event Value

KeyEventHandler

PopupClosed

Occurs when the drop-down popup has been fully closed. This event is raised after the popup is no longer visible to the user. The event arguments contain information about the cause of the closing action, which can be used to perform different operations based on how the popup was closed.

Declaration

cs-api-definition
public virtual event RadPopupClosedEventHandler PopupClosed

Event Value

RadPopupClosedEventHandler

PopupClosing

Occurs just before the drop-down popup is about to be closed. This event provides an opportunity to cancel the closing operation or to perform cleanup operations before the popup disappears. The event arguments contain information about the cause of the closing action.

Declaration

cs-api-definition
public virtual event RadPopupClosingEventHandler PopupClosing

Event Value

RadPopupClosingEventHandler

PopupOpened

Occurs when the drop-down popup has been fully opened and displayed to the user. This event can be used to perform initialization tasks after the popup becomes visible, such as adjusting scroll position or focusing specific items.

Declaration

cs-api-definition
public virtual event EventHandler PopupOpened

Event Value

EventHandler

PopupOpening

Occurs just before the drop-down popup is displayed to the user. This event can be used to cancel the opening of the popup or to perform last-minute modifications to the items displayed in the list before they become visible.

Declaration

cs-api-definition
public virtual event CancelEventHandler PopupOpening

Event Value

CancelEventHandler

SelectedIndexChanged

Occurs when the index of the currently selected item in the drop-down list changes. This event is raised when the user selects a new item from the list or when the SelectedIndex property is programmatically changed. The event arguments provide information about the previous and current selection position.

Declaration

cs-api-definition
public event PositionChangedEventHandler SelectedIndexChanged

Event Value

PositionChangedEventHandler

SelectedIndexChanging

Occurs just before the selected index in the drop-down list is about to change. This event allows you to cancel the selection change by setting the Cancel property of the event arguments to true, providing a way to validate or restrict item selection based on custom business logic.

Declaration

cs-api-definition
public event PositionChangingEventHandler SelectedIndexChanging

Event Value

PositionChangingEventHandler

SelectedValueChanged

Occurs when the value of the currently selected item in the drop-down list changes. Unlike the SelectedIndexChanged event, this event only fires when the actual value changes, not just the index. For example, if two different items in the list have the same value, selecting between them will not trigger this event.

Declaration

cs-api-definition
public event EventHandler SelectedValueChanged

Event Value

EventHandler

SortStyleChanged

Occurs when the sorting style of the drop-down list items changes. This event allows you to respond to changes in how items are sorted in the list, which can be useful for performing additional operations after the sort order has changed.

Declaration

cs-api-definition
public event SortStyleChangedEventHandler SortStyleChanged

Event Value

SortStyleChangedEventHandler

TextChanged

Occurs when the Text property value changes. This event is raised after the text displayed in the control is modified either by user input or programmatically.

Declaration

cs-api-definition
public event EventHandler TextChanged

Event Value

EventHandler

VisualListItemFormatting

Occurs when a visual list item needs to be formatted. This event fires when a property of a visible data item changes or when a visual item is associated with a new data item (such as during scrolling). It provides the opportunity to customize the appearance of list items based on their content or state.

Declaration

cs-api-definition
public event VisualListItemFormattingEventHandler VisualListItemFormatting

Event Value

VisualListItemFormattingEventHandler

In this article
DefinitionConstructorsRadDropDownList()FieldsCreatingVisualListItemEventKeyKeyDownEventKeyKeyPressEventKeyKeyUpEventKeyListItemDataBindingEventKeyListItemDataBoundEventKeyPopupClosedEventKeyPopupClosingEventKeyPopupOpenedEventKeyPopupOpeningEventKeySelectedIndexChangedEventKeySelectedIndexChangingEventKeySelectedValueChangedEventKeySelectionRangeChangedKeySortStyleChangedKeyVisualItemFormattingKeyPropertiesAllowShowFocusCuesAutoCompleteDataSourceAutoCompleteDisplayMemberAutoCompleteModeAutoCompleteValueMemberAutoSizeAutoSizeItemsCaseSensitiveCausesValidationDataMemberDataSourceDefaultItemsCountInDropDownDefaultSizeDescriptionTextMemberDisplayMemberDropDownAnimationEasingDropDownAnimationEnabledDropDownAnimationFramesDropDownHeightDropDownListElementDropDownMaxSizeDropDownMinSizeDropDownSizingModeDropDownStyleEnableAlternatingItemColorEnableKineticScrollingEnableMouseWheelEnableUIAutomationFilterFilterExpressionFindStringComparerFitItemsToSizeFontFormatInfoFormatStringFormattingEnabledIsFilterActiveIsPopupVisibleItemHeightItemsItemsSortComparerListElementMaxDropDownItemsMaxLengthNullTextPopupReadOnlySelectNextOnDoubleClickSelectedIndexSelectedItemSelectedItemsSelectedTextSelectedValueSelectionLengthSelectionStartShowImageInEditorAreaSortStyleTabStopTextUIAutomationProviderValueMemberMethodsBeginUpdate()CloseDropDown()ControlDefinesThemeForElement(RadElement)CreateAccessibilityInstance()CreateChildItems(RadElement)CreateDropDownListElement()CreateRootElement()DeferRefresh()Dispose(bool)EndInit()EndUpdate()FindItemExact(string, bool)FindString(string)FindString(string, int)FindStringExact(string)FindStringExact(string, int)FindStringNonWrapping(string)FindStringNonWrapping(string, int)IsInputChar(char)IsInputKey(Keys)OnBindingContextChanged(EventArgs)OnCreatingVisualItem(object, CreatingVisualListItemEventArgs)OnDataBindingComplete(object, ListBindingCompleteEventArgs)OnEnter(EventArgs)OnGotFocus(EventArgs)OnItemDataBinding(object, ListItemDataBindingEventArgs)OnItemDataBound(object, ListItemDataBoundEventArgs)OnLeave(EventArgs)OnLostFocus(EventArgs)OnRightToLeftChanged(EventArgs)OnSelectedIndexChanged(object, int)OnSelectedIndexChanging(object, int)OnSelectedValueChanged(object, int, object, object)OnSortStyleChanged(SortStyle)OnVisualItemFormatting(RadListVisualItem)ProcessAutoSizeChanged(bool)ProcessCodedUIMessage(ref IPCMessage)Rebind()ResetBackColorThemeOverrides()ResetForeColorThemeOverrides()SelectAll()SelectAllText()SelectText(int, int)SetBackColorThemeOverrides()SetForeColorThemeOverrides()ShowDropDown()WndProc(ref Message)dropDownListElement_KeyDown(object, KeyEventArgs)dropDownListElement_KeyPress(object, KeyPressEventArgs)dropDownListElement_KeyUp(object, KeyEventArgs)element_PopupClosed(object, RadPopupClosedEventArgs)element_PopupClosing(object, RadPopupClosingEventArgs)element_PopupOpened(object, EventArgs)element_PopupOpening(object, CancelEventArgs)EventsCreatingVisualListItemDataBindingCompleteItemDataBindingItemDataBoundKeyDownKeyPressKeyUpPopupClosedPopupClosingPopupOpenedPopupOpeningSelectedIndexChangedSelectedIndexChangingSelectedValueChangedSortStyleChangedTextChangedVisualListItemFormatting
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