How to do Email validation!!!!!!!

U can go with the following code.

 private void txtEmail_Validating(object sender, CancelEventArgs e)
        {
            System.Text.RegularExpressions.Regex rEMail = 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 (txtEmail.Text.Length > 0)
            {

                if (!rEMail.IsMatch(txtEmail.Text))
                {

                    MessageBox.Show("Please provide valid email address", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);

                    txtEmail.SelectAll();

                }
            }

        }