How to validate email ID in c#.net Windows application?

How to validate email textbox in C# ?

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Collections;
namespace Project_Windows
{
    public partial class Form1: Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            int status = ValidateEmailId(textBox1.Text);
            if (status == 0)
            {
                MessageBox.Show("E-Mail Id expected", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
            else if (status == 1)
            {
                MessageBox.Show("Thanks for ptoviding a valid E-mail Id. ", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
            else if (status == 2)
            {
                MessageBox.Show("Please enter a Valid E-mail Id", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
            }

        }
        public int ValidateEmailId(string emailId)
        {
            
            System.Text.RegularExpressions.Regex rEMail = new System.Text.RegularExpressions.Regex(@"^[a-zA-Z][\w\.-]{2,28}[a-zA-Z0-9]@[a-zA-Z0-9][\w\.-]*[a-zA-Z0-9]\.[a-zA-Z][a-zA-Z\.]*[a-zA-Z]$");
            if (emailId.Length > 0)
            {
                if (!rEMail.IsMatch(emailId))
                {
                    return 0;
                }
                else
                {
                    return 1;
                }
            }
            return 2;
        }
    }
}