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View Sample
<html>
<head>
<title>RequiredFieldValidator Example</title>
<link rel="stylesheet" href="/shared/netdemos.css">

<script language="C#" runat="server">
void greetUser ( object src, EventArgs e ) {
   if ( Page.IsValid ) {
      message.InnerHtml = "Hello, " + userName.Text +
         "<br>Welcome to Web Forms Validation";
   }
}
</script>
</head>

<body>
<!-- #include virtual="~/shared/top.inc -->
<div class="header"><h2>RequiredFieldValidator Example</span></h2></div>

<!-- #include virtual="~/shared/viewsrc_top.inc" -->
<hr size=1 width=92%>

<div align="center">
<form runat="server">

   <p>Enter your name: <asp:textbox id="userName" runat="server" />

   <asp:button text="Enter" onClick="greetUser" runat="server" />

   <p><asp:requiredfieldvalidator
      controltovalidate="userName"
      display="dynamic"
      errormessage="Sorry, but I need to know your name."
      forecolor="blue" font-bold
      runat="server" /></p>

   <p id="message" runat="server" />

</form>
</div>

<hr size=1 width=92%>
<!-- #include virtual="~/shared/viewsrc.inc" -->

</body>
</html>