Control.IsLiteralContent Method

// Override the OnLoad method to check if the  
// page that uses this control has posted back. 
// If so, check whether this controls contains 
// only literal content, and if it does, 
// it gets the UniqueID property and writes it 
// to the page. Otherwise, it writes a message 
// that the control contains more than literal content. 
protected override void OnLoad(EventArgs e)
{
        if (Page.IsPostBack)
        {
                String s;

                if (this.IsLiteralContent())
                {
                        s = Controls[0].UniqueID;
                        Context.Response.Write(s);
                }
                else
                {
                        Context.Response.Write(
                                "The control contains more than literal content.");
                }
        }
}