Using the CustomValidator control to perform client-side validations : CustomValidator « Validation « ASP.NET Tutorial
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- Validation
- CustomValidator
<%@ Page Language="C#" %>
<script runat="server">
protected void Button1_Click(Object sender, EventArgs e) {
Label1.Text = "VALID NUMBER!";
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>CustomValidator</title>
<script language="JavaScript">
function validateNumber(oSrc, args) {
args.IsValid = (args.Value % 5 == 0);
}
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
Number:
<asp:TextBox ID="TextBox1"
Runat="server"></asp:TextBox>
<asp:CustomValidator ID="CustomValidator1"
Runat="server" ControlToValidate="TextBox1"
ErrorMessage="Number must be divisible by 5"
ClientValidationFunction="validateNumber">
</asp:CustomValidator>
<asp:Button ID="Button1" OnClick="Button1_Click"
Runat="server" Text="Button"></asp:Button>
<asp:Label ID="Label1" Runat="server"></asp:Label>
</div>
</form>
</body>
</html>