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;
      }