messagebox in ASP.NET 2.0

The basic concept is to use JavaScript. Below only shows one way of implementing javascript for messagebox:

switch (txtName.Value)
{
case ("aaa"):
Page.ClientScript.RegisterStartupScript(this.GetType(),"Alert","< script language="javascript" >alert('AAA');< /script >
");
break;

case ("bbb"):
Page.ClientScript.RegisterStartupScript(this.GetType(), "Alert", "< script language="javascript" >alert('BBB');< /script >
");
break;


}