Using the CustomValidator control to perform server-side validations (C#) : CustomValidator « Validation « ASP.NET Tutorial






  1. ASP.NET Tutorial
  2. Validation
  3. CustomValidator
<%@ Page Language="C#" %>

<script runat="server">

    protected void Button1_Click(Object sender, EventArgs e) {
         if (Page.IsValid) {
            Label1.Text = "VALID ENTRY!";
         }
    }

    void ValidateNumber(object source, ServerValidateEventArgs args)
    {
       try 
       {
          int num = int.Parse(args.Value);
          args.IsValid = ((num%5) == 0);
       }
       catch(Exception ex)
       {
          args.IsValid = false;
       }
    }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>CustomValidator</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        
            Number: 
            <asp:TextBox ID="TextBox1" 
             Runat="server"></asp:TextBox>
             &nbsp;
            <asp:CustomValidator ID="CustomValidator1" 
             Runat="server" ControlToValidate="TextBox1" 
             ErrorMessage="Number must be divisible by 5" 
             OnServerValidate="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>








8.3.CustomValidator
8.3.1.You can associate a custom validation function with the CustomValidator control.
8.3.2.Validate a blank field
8.3.3.Performing validation against no particular field.
8.3.4.Use both client side and server side script to validate (VB.net)
8.3.5.Create user control based on CustomValidator
8.3.6.Using the CustomValidator control to perform client-side validations
8.3.7.Using the CustomValidator control to perform server-side validations (C#)
8.3.8.Using the CustomValidator control to perform server-side validations (VB)
8.3.9.Custom validator with Javascript
8.3.10.CustomValidator for login page
8.3.11.CustomValidator for login page (VB)