RadDropDownList

Set this property to true if the server needs to capture the selection as soon as it is made. For example, other controls on the Web page can be automatically filled depending on the user's selection from a list control.

This property can be used to allow automatic population of other controls on the Web page based on a user's selection from a list.

The value of this property is stored in view state.

Use the CollapseAnimation property to customize the expand animation of RadDropDownList. You can specify the Type and Duration. To disable collapse animation effects you should set the Type to AnimationType.None.
To customize the expand animation you can use the ExpandAnimation property.

When set to true upon scroll a request will be made either to the server or to a web service in order to render and initialize a new set of items

Use the ExpandAnimation property to customize the expand animation of RadDropDownList. You can specify the Type and Duration. To disable expand animation effects you should set the Type to AnimationType.None.
To customize the collapse animation you can use the CollapseAnimation property.

When this property is not set the number Items which will be loaded will be calculated based on the height of the DropDrown of the RadDropDownList and the height of a single item.

You can use the Items property to add and remove items in the RadDropDownList control.

The event handler receives two parameter: the instance of the dropdownlist client-side object and event args. The event can not be cancelled

The event handler receives two parameter: the instance of the dropdownlist client-side object and event args. The event can be cancelled - simply set args.set_cancel to true args.set_cancel(true); from the event handler and the dropdownlist dropdown will not be closed.

The event handler receives two parameter: the instance of the dropdownlist client-side object and event args. The event cannot be cancelled.

The event handler receives two parameter: the instance of the dropdownlist client-side object and event args. The event can be cancelled - simply set args.set_cancel to true args.set_cancel(true); from the event handler and the dropdownlist dropdown will not be opened.

The event handler receives two parameters: the instance of of the dropdownlist client-side object and event argument with get_dateItem() and get_item() methods.

The event handler receives two parameters: the instance of of the dropdownlist client-side object and event argument with the item which is selected.

The event handler receives two parameters: the instance of of the dropdownlist client-side object and event argument with the item which is about to be selected and set_cancel method.The event can be cancelled.

If specified, the OnClientItemsRequested client-side event handler is called when the RadDropDownList items were just populated. Two parameters are passed to the handler:

• sender, the menu client object;
• eventArgs, null for this event.

This event cannot be cancelled.

If specified, the OnClientItemsRequestFailed client-side event handler is called when the operation for populating the RadDropDownList has failed. Two parameters are passed to the handler:

• sender, the menu client object;
• eventArgs with one property:
  • set_cancel(), set to true to suppress the default action (alert message).

This event can be cancelled.

If specified, the OnClientItemsRequesting client-side event handler is called when the RadDropDownList is about to send a request for items. Two parameters are passed to the handler:

• sender, the dropdownlist client object;
• eventArgs with two properties:
  • get_context(), an user object that will be passed to the web service.
  • set_cancel(), used to cancel the event.

This event can be cancelled.

If specified, the OnClienLoad client-side event handler is called after the dropdownlist is fully initialized on the client.

A single parameter - the dropdownlist client object - is passed to the handler.

This event cannot be cancelled.

The event handler receives two parameters: the instance of of the dropdownlist client-side object and event argument with the new selected index.

The event handler receives two parameters: the instance of of the dropdownlist client-side object and event argument with get_dateItem(), get_html(), set_html() and get_template() methods.

Set the selected index to -1 to clear the selection.

SelectedItem can be null in client-side binding scenarios.

Use the WebServiceSettings property to configure the web service used to populate items on demand. You must specify both Path and Method to fully describe the service.

In order to use the integrated support, the web service should have the following signature:

   <pre><code class="lang-csharp">[ScriptService]

public class WebServiceName : WebService { private static int totalCount = 100; private static List<DropDownListItemData> itemsList = new List<DropDownListItemData>();

static DropDownService() { for (var i = 0; i < totalCount; i++) { DropDownListItemData itemData = new DropDownListItemData(); itemData.Text = "Item" + i.ToString(); itemData.Value = i.ToString(); itemData.Attributes["Attribute"] = "Attribute" + i.ToString(); itemsList.Add(itemData); } }

[WebMethod] public DropDownListData GetItems(DropDownListContext context) { DropDownListData data = new DropDownListData(); data.Items = itemsList.GetRange(context.StartIndex, context.ItemsCount).ToArray(); data.TotalCount = totalCount;

 return data;

} }

<System.Web.Script.Services.ScriptService()> _
Public Class WebService
Inherits System.Web.Services.WebService


   Private Shared totalCount As Integer = 100
   Private Shared itemsList As New List(Of DropDownListItemData)()

   Shared Sub New()
       For i As Integer = 0 To totalCount - 1
           Dim itemData As New DropDownListItemData()
           itemData.Text = "Item" + i.ToString()
           itemData.Value = i.ToString()
           itemData.Attributes("Attribute") = "Attribute" + i.ToString()
           itemsList.Add(itemData)

       Next
   End Sub

   <WebMethod> _
   Public Function GetItems(context As DropDownListContext) As DropDownListData
       Dim data As New DropDownListData()
       data.Items = itemsList.GetRange(context.StartIndex, context.ItemsCount).ToArray()
       data.TotalCount = totalCount

       Return data
   End Function

End Class

Can be used when the dropdown is to be shown over content with a specified Z-index. If the dropdownlist items dropdown is displayed below the content, set the ZIndex property to a value higher than the value of the HTML content below.

The string to search for.

A Boolean indicating a case-sensitive or insensitive comparison (true indicates a case-insensitive comparison).

The string to search for.

The value to search for.

A Boolean indicating a case-sensitive or insensitive comparison (true indicates a case-insensitive comparison).

The value to search for.

Name of the XML file.

The key identifier for the control, used to index the postCollection.

A NameValueCollection that contains value information indexed by control identifiers.

The DropDownListItemEventArgs instance containing the event data.

The DropDownListItemEventArgs instance containing the event data.

The DropDownListEventArgs instance containing the event data.

The DropDownListEventArgs instance containing the event data.

The DropDownListItemEventArgs instance containing the event data.

The ItemCreated event occurs before ItemDataBound and after postback if ViewState is enabled. ItemCreated is not raised for items defined inline in the ASPX.

Use the ItemDataBound event to set additional properties of the databound items.

The TemplateNeeded event is raised before a template is been applied on the item, both during round-trips (postbacks) and at the time data is bound to the control. The TemplateNeeded event is not raised for items which are defined inline in the page or user control.

The TemplateNeeded event is commonly used for dynamic templating.