Mega Code Archive
A simple use of the RequiredFieldValidator server control (C#)
<![CDATA[
<%@ Page Language="C#" %>
<script runat="server">
protected void Button1_Click(Object sender, EventArgs e) {
Label1.Text = "Page is valid!";
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>RequiredFieldValidator</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:TextBox ID="TextBox1" Runat="server"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator1"
Runat="server"
ErrorMessage="Required!"
ControlToValidate="TextBox1">
</asp:RequiredFieldValidator>
<asp:Button ID="Button1"
Runat="server"
Text="Submit"
OnClick="Button1_Click" />
<asp:Label ID="Label1" Runat="server"></asp:Label>
</div>
</form>
</body>
</html>
]]>