RequiredFieldValidator with server side validation : RequiredFieldValidator « Validation « ASP.NET Tutorial






<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="Login" %>

<!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>Simple Login Page</title>
</head>
<body>
    <form id="form1" runat="server">
    Username:<br />
          <asp:TextBox id="usernameTextBox" runat="server" />
          <asp:RequiredFieldValidator id="usernameReq"
              runat="server"
              ControlToValidate="usernameTextBox"
              ErrorMessage="Username is required!"
              SetFocusOnError="True" />
    Password:<br />
          <asp:TextBox id="passwordTextBox" 
              runat="server"
              TextMode="Password" />
          <asp:RequiredFieldValidator id="passwordReq"
              runat="server"
              ControlToValidate="passwordTextBox"
              ErrorMessage="Password is required!"
              SetFocusOnError="True" />
          <asp:Button id="submitButton" 
              runat="server"
              Text="Submit" 
              OnClick="submitButton_Click" />
    </form>
</body>
</html>

File: Default.aspx.cs

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class Login : System.Web.UI.Page
{
    protected void submitButton_Click(object sender, EventArgs e)
    {
        if (Page.IsValid)
        {
            submitButton.Text = "Valid";
        }
        else
        {
            submitButton.Text = "Invalid!";
        }
    }
}








8.11.RequiredFieldValidator
8.11.1.RequiredFieldValidator requires a user to enter a value into a form field before submitting the form.
8.11.2.Use asp:RequiredFieldValidator to check the input of an asp:TextBox (VB.net)
8.11.3.Use the RequiredFieldValidator's InitialValue to set a default value
8.11.4.Specify ErrorMessage for asp:RequiredFieldValidator
8.11.5.asp:RequiredFieldValidator will be converted to JavaScript Code after loading in client side
8.11.6.A simple use of the RequiredFieldValidator server control (C#)
8.11.7.Text field of RequiredFieldValidator server control (VB)
8.11.8.Placing values between nodes
8.11.9.Working with the InitialValue property
8.11.10.Using two RequiredFieldValidator controls for one form element
8.11.11.Validating Drop-Down Lists with the RequiredFieldValidator Control
8.11.12.Using images for error notifications
8.11.13.Disabling client-side validations in a validation control
8.11.14.Using sound for error notifications
8.11.15.EnableClientScript=false, Display=Static
8.11.16.RequiredFieldValidator for login page
8.11.17.RequiredFieldValidator with server side validation
8.11.18.Hard code error message
8.11.19.RequiredFieldValidator Dynamic Display