email Validation in Javascript

var email = $("#<%= txtEmail.ClientID %>").val().trim();
                var emlExp = /^([\w-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$/;
                if (!email.match(emlExp)) {
}