TemplatedControlDesigner.OnComponentChanged Method
A delegate that handles the component changed event.
[Visual Basic] Overrides Public Sub OnComponentChanged( _ ByVal sender As Object, _ ByVal ce As ComponentChangedEventArgs _ ) [C#] public override void OnComponentChanged( object sender, ComponentChangedEventArgs ce ); [C++] public: void OnComponentChanged( Object* sender, ComponentChangedEventArgs* ce ); [JScript] public override function OnComponentChanged( sender : Object, ce : ComponentChangedEventArgs );
Parameters
- sender
- The object sending the event.
- ce
- A ComponentChangedEventArgs that provides data for the event.
Remarks
This is called after a property has been changed. It allows the implementor to do any post-processing that may be needed after a property change.
Example
[Visual Basic] The following code example overrides the OnComponentChanged method to check the name of the property that changed. If the name was DataSource or DataMember, then a custom method, named OnDataSourceChanged, is called that sets the data table used at design time to a null reference (Nothing in Visual Basic). If the name was ItemStyle, then a custom method, named OnStylesChanged, is called that in turn calls a method that notifies the designer that the template editing verbs collection associated with the designer has changed.
[Visual Basic]
' Override the OnComponentChanged method to change
' the control's DataSource or styles in the designer.
Public Overrides Sub OnComponentChanged(sender As Object, e As ComponentChangedEventArgs)
If Not (e.Member Is Nothing) Then
Dim memberName As String = e.Member.Name
If memberName.Equals("DataSource") Or memberName.Equals("DataMember") Then
OnDataSourceChanged()
Else
If memberName.Equals("ItemStyle") Then
OnStylesChanged()
End If
End If
End If
MyBase.OnComponentChanged(sender, e)
End Sub
' Create a method that sets the data table
' associated with the templates to nothing.
Protected Overridable Sub OnDataSourceChanged()
designTimeDataTable = Nothing
End Sub
' Create a method that determines whether the designer
' verbs associated with the control's templates have
' changed.
Protected Sub OnStylesChanged()
OnTemplateEditingVerbsChanged()
End Sub
' Create a method that notifies all callers
' that the designer verbs collection has changed.
Protected Sub OnTemplateEditingVerbsChanged()
templateVerbsDirty = True
End Sub
[C#, C++, JScript] No example is available for C#, C++, or JScript. To view a Visual Basic example, click the Language Filter button
in the upper-left corner of the page.
Requirements
Platforms: Windows 2000, Windows XP Professional, Windows Server 2003 family
.NET Framework Security:
- Full trust for the immediate caller. This member cannot be used by partially trusted code. For more information, see Using Libraries From Partially Trusted Code
See Also
TemplatedControlDesigner Class | TemplatedControlDesigner Members | System.Web.UI.Design Namespace