how to handle GridDropDownColumn change event at server side inside MasterTableView column in radgrid Aspx

[Kiran]

Iam using telerik grid of asp.net

I want to disable column "telerik:GridNumericColumn " in below code snippet on changing "telerik:GridDropDownColumn" I am not aware of how to handle selection change event of GridDropDownColumn on server side and make one column disabled.

Please help in this regard.

Regards, Kiran

 

Below is the radgrid declaration

<telerik:RadGrid ID="rg" runat="server"
                                                AllowSorting="False"
                                                AutoGenerateColumns="False" Width="730px" Height="263px"
                                                OnUpdateCommand="rg_Update"
                                                OnInsertCommand="rg_Insert"
                                                OnDeleteCommand="rg_Delete"
                                                OnItemCreated="rg_ItemCreated"
                                                OnItemCommand="rg_ItemCommand"
                                                OnSelectedIndexChanged="rg_SelectedIndexChanged"
                                                OnNeedDataSource="rg_NeedDataSource"
                                                OnDataBound="rg_DataBound"
                                                GridLines="None"
                                                CellSpacing="0"
                                                MasterTableView-Caption="Routing Rules">
                                                <ClientSettings AllowKeyboardNavigation="true" EnablePostBackOnRowClick="true">
                                                    <Scrolling AllowScroll="True" UseStaticHeaders="True" />
                                                    <Selecting AllowRowSelect="True" />
                                                </ClientSettings>

                                                <MasterTableView CommandItemDisplay="Top" DataKeyNames="Id,IndexId">
                                                    <CommandItemSettings AddNewRecordText="Add New Routing Rule" />
                                                    <Columns>
                                                        <telerik:GridButtonColumn UniqueName="editButton" ButtonType="ImageButton" CommandName="Edit" FilterControlAltText="Filter editButton column"
                                                            HeaderText="Edit" HeaderStyle-Width="34px" ItemStyle-HorizontalAlign="Left" Resizable="false"
                                                            ImageUrl="~\Images\pencil.png">
                                                        </telerik:GridButtonColumn>
                                                        <telerik:GridButtonColumn UniqueName="deleteButton" ButtonType="ImageButton" CommandName="Delete" FilterControlAltText="Filter deleteButton column"
                                                            HeaderText="Delete" HeaderStyle-Width="47px" ItemStyle-HorizontalAlign="Left" Resizable="false"
                                                            ImageUrl="~\Images\delete.png"
                                                            ConfirmDialogType="RadWindow" ConfirmText="Are you sure you want to delete this record?">
                                                        </telerik:GridButtonColumn>
                                                        <telerik:GridBoundColumn Visible="false" DataField="Id" UniqueName="RoutingRuleRuleId" ReadOnly="True" />
                                                        <telerik:GridNumericColumn DataField="Priority" UniqueName="RoutingRulePriority" HeaderText="Priority" DataType="System.Int32" MaxLength="3" />

                                                        <telerik:GridDropDownColumn
                                                            HeaderText="Rule Type" DataField="RoutingRuleDefinitionId" SortExpression="uRuleType" UniqueName="uRuleType"
                                                            ColumnEditorID="myRuleTypeDropDownEditor"
                                                            ListTextField="Name" ListValueField="Id" EnableEmptyListItem="True"
                                                            EmptyListItemValue="0" Visible="False">
                                                        </telerik:GridDropDownColumn>
</MasterTableView>
</telerik:RadGrid>

[Kiran]

Can we achieve this with GridDropDownColumn?

[Doncho]

Hi Kiran,

By default, the GridDropDownColumn renders a RadComboBox (or a DropDownList, if it is set as the DropDownControlType). You can access this edit control programmatically and subscribe to its SelectedIndexChanged event to execute the desired custom logic upon changing the selection:

Here are some relevant resources:

• https://docs.telerik.com/devtools/aspnet-ajax/controls/grid/server-side-programming/events/itemcreated
• https://docs.telerik.com/devtools/aspnet-ajax/controls/grid/accessing-values-and-controls/server-side/accessing-controls#accessing-controls-of-built-in-columns 
• https://docs.telerik.com/devtools/aspnet-ajax/controls/grid/data-editing/distinguish-edit-or-insert-mode 
• https://www.telerik.com/forums/griddropdowncolumn-autopostback-on-selectedindex-change#1116591 

I hope this will help you achieve the desired.

Please let me know if any further questions come up.

Kind regards,
Doncho
Progress Telerik