Show Message in ASP.Net 2.0

public void showmessage(string strMessage)
{
//String strScript = "" ;

//if(! ClientScript.IsStartupScriptRegistered("clientScript"))
// ClientScript.RegisterClientScriptBlock(this.GetType(), "clientScript", strScript);
Label lbl = new Label();
lbl.Text = "";
// add the label to the page to display the alertbox
//Page.Controls.Add(lbl);

}