<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title>Untitled Page</title>
<script language="javascript" type="text/javascript">
function Hello()
{
alert("Hello");
}
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:Button ID="Button1" runat="server" Text="Button" onclick="Button1_Click"/>
</div>
</form>
</body>
</html>
protected void Button1_Click(object sender, EventArgs e)
{
Page.ClientScript.RegisterStartupScript(this.GetType(), "alert1", "Hello();", true);
}