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ToolboxComponentsCreatingEventHandler Delegate

Represents the method that handles the ComponentsCreating event.

[Visual Basic]
Public Delegate Sub ToolboxComponentsCreatingEventHandler( _
   ByVal sender As Object, _
   ByVal e As ToolboxComponentsCreatingEventArgs _
public delegate void ToolboxComponentsCreatingEventHandler(
   object sender,
   ToolboxComponentsCreatingEventArgs e
public __gc __delegate void ToolboxComponentsCreatingEventHandler(
   Object* sender,
   ToolboxComponentsCreatingEventArgs* e

[JScript] In JScript, you can use the delegates in the .NET Framework, but you cannot define your own.

Parameters [Visual Basic, C#, C++]

The declaration of your event handler must have the same parameters as the ToolboxComponentsCreatingEventHandler delegate declaration.

The source of the event.
A ToolboxComponentsCreatingEventArgs that provides data for the event.


When you create a ToolboxComponentsCreatingEventHandler delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event-handler delegates, see Events and Delegates.


[Visual Basic, C#, C++] The following example code provides a method that attaches an event handler for the ComponentsCreating event of a ToolboxItem, and a ToolboxComponentsCreatingEventHandler event handler method that writes the name of the type of the component that is to receive the new component or components to the Console when the event handler is raised by a ComponentsCreating event.

[Visual Basic] 
Public Sub LinkToolboxComponentsCreatingEvent(ByVal item As ToolboxItem)
    AddHandler item.ComponentsCreating, AddressOf Me.OnComponentsCreating
End Sub

Private Sub OnComponentsCreating(ByVal sender As Object, ByVal e As ToolboxComponentsCreatingEventArgs)
    ' Displays ComponentsCreating event information on the Console.
    Console.WriteLine(("Name of the class of the root component of the designer host receiving new components: " + e.DesignerHost.RootComponentClassName))
End Sub

public void LinkToolboxComponentsCreatingEvent(ToolboxItem item)
    item.ComponentsCreating += new ToolboxComponentsCreatingEventHandler(this.OnComponentsCreating);

private void OnComponentsCreating(object sender, ToolboxComponentsCreatingEventArgs e)
    // Displays ComponentsCreating event information on the Console.
    Console.WriteLine("Name of the class of the root component of " +
    "the designer host receiving new components: " +

    void LinkToolboxComponentsCreatingEvent(ToolboxItem* item) {
        item->ComponentsCreating += new ToolboxComponentsCreatingEventHandler(this, &Form1::OnComponentsCreating);

    void OnComponentsCreating(Object* /*sender*/, ToolboxComponentsCreatingEventArgs* e) {
        // Displays ComponentsCreating event information on the Console.
        Console::WriteLine(S"Name of the class of the root component of the designer host receiving new components: {0}",

[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button Language Filter in the upper-left corner of the page.


Namespace: System.Drawing.Design

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

Assembly: System.Drawing (in System.Drawing.dll)

See Also

System.Drawing.Design Namespace | ToolboxComponentsCreatingEventArgs | ComponentsCreating