Sorry, I guess I misunderstood your question the first time.

You can try spinnning through the Controls collection maybe?

foreach (Control o in this.Controls)
{
	if (o is MyControl)
	{
		// then it's been added already
	}
}

~~Bonnie



>Hi,
>Thank you for reply.
>Then, how could I know the control is already added to form or not?
>
>Thank you