Check email using Jquery

var email = $("#txtEmail").val();

 var regex = /^([a-zA-Z0-9_\.\-\+])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
            if (!regex.test(email )) {
                alert("You must enter a valid e-mail address");
                return false;
            }