public void AddButton()
{
// Add a standard button.
Button b = new Button();
b.Text = "New standard button";
RootDesigner.AddControlToDocument(b, null, ControlLocation.First);
}
public void AddNewButton()
{
// Add your custom button.
NewButton b = new NewButton();
b.Text = "New custom button";
// For buttons defined in a different assembly, add the
// register directive for the referenced assembly.
// assembly. By default, this goes to the document, unless
// already defined in the document or in configuration.
WebFormsReferenceManager wfrm =
RootDesigner.ReferenceManager;
wfrm.RegisterTagPrefix(b.GetType());
RootDesigner.AddControlToDocument(b, null, ControlLocation.Last);
}