' Override the CreateControlCollection method to  
        ' write to the Trace object when tracing is enabled 
        ' for the page or application in which this control 
        ' is included.    
        Protected Overrides Function CreateControlCollection() As ControlCollection
            Return New CustomControlCollection(Me)
        End Function

// Override the CreateControlCollection method to  
		// write to the Trace object when tracing is enabled 
		// for the page or application in which this control 
		// is included.    
		protected override ControlCollection CreateControlCollection()
		{
			return new CustomControlCollection(this);
		}

Protected Overrides Sub CreateChildControls()
   ' Creates a new ControlCollection.  
   Me.CreateControlCollection()

   ' Create child controls. 
   Dim firstControl As New ChildControl()
   firstControl.Message = "FirstChildControl" 

   Dim secondControl As New ChildControl()
   secondControl.Message = "SecondChildControl"

   Controls.Add(firstControl)
   Controls.Add(secondControl)

   ' Prevent child controls from being created again.
   ChildControlsCreated = True 
End Sub 'CreateChildControls

protected override void CreateChildControls()
      {               
         // Creates a new ControlCollection.  
         this.CreateControlCollection();

         // Create child controls.
          ChildControl firstControl = new ChildControl();
         firstControl.Message = "FirstChildControl";

         ChildControl secondControl = new ChildControl();
         secondControl.Message = "SecondChildControl";

         Controls.Add(firstControl);
         Controls.Add(secondControl);

         // Prevent child controls from being created again.
         ChildControlsCreated = true;
      }