i solved it
protected void Page_Load(object sender, EventArgs e)
{
String script = @"<script language=""Javascript"">
function TestJScript()
{
alert('Just for testing');
}
</script>";
Page.RegisterClientScriptBlock("experiment", script);
Button3.Attributes.Add("onClick", "TestJScript()");
}
when you click on the Button3 the javascript function is running
and another way:
Button3.Attributes.Add("onclick", "javascript:alert('Testing Macro Functionality');");
and another way:
Response.Write("<script language=javascript>confirm(\"Are you sure to change?\");</script>");