Email Address Validation To Window Application C#

Email Address Validation To Window Application C#

Email Address Enter To Textbox Validation Check Suppose Error Occur Open Popup Using window Application C#.

                                DEMO

                           
                          C# CODING

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Windows.Forms;

namespace WindowsFormsApplication2

{

    public partial class Email : Form

    {

        public Email()

        {

            InitializeComponent();

        }    

                  

      private void txtEmailId_Validating(object sender, CancelEventArgs e)

        {

            System.Text.RegularExpressions.Regex RegEmail =

              new System.Text.RegularExpressions.Regex(@"^[a-zA-Z][\w\.-]*[a-zA-Z0-9]@[a-zA-Z0-9][\w\.-]*[a-zA-Z0-9]\.[a-zA-Z][a-zA-Z\.]*[a-zA-Z]$");

            if (txtEmailId.Text.Length > 0 && txtEmailId.Text.Trim().Length != 0)

            {

                if (!RegEmail.IsMatch(txtEmailId.Text.Trim()))

                {

                    MessageBox.Show("Invalid Email Id", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);

                    txtEmailId.SelectAll();

                    //e.Cancel = true;

                }

            }

        }

    }

}

First - Add New Form - Add TextBox From ToolBox - Change The Id

Next - TextBox Event - Click - Double Click Validating Button

Next - Invalid Email Id Enter Check Regular Expression Condition 

Next - Run[F5] - The Program  Enter Email Id - Invalid Enter Error Box Open