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ControlDesigner.OnComponentChanged Method

Called when the component changes.

[Visual Basic]
Public Overridable Sub OnComponentChanged( _
   ByVal sender As Object, _
   ByVal ce As ComponentChangedEventArgs _
)
[C#]
public virtual void OnComponentChanged(
 object sender,
 ComponentChangedEventArgs ce
);
[C++]
public: virtual void OnComponentChanged(
 Object* sender,
 ComponentChangedEventArgs* ce
);
[JScript]
public function OnComponentChanged(
   sender : Object,
 ce : ComponentChangedEventArgs
);

Parameters

sender
The source of the event.
ce
A ComponentChangedEventArgs that contains the event data.

Remarks

This method is called when a property is changed. It allows the implementer to do any processing that may be needed after a property change.

Example

[Visual Basic] The following code example overrides the OnComponentChanged method in a templated data-bound control designer. The code processes changes to the control's DataSource property value and changes to the control's Style property.

[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 Language Filter in the upper-left corner of the page.

Requirements

Platforms: Windows 2000, Windows XP Professional, Windows Server 2003 family

.NET Framework Security: 

See Also

ControlDesigner Class | ControlDesigner Members | System.Web.UI.Design Namespace | ComponentChanged

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