jQuery驗證表單電子郵件地址的有效性

<!-- jQuery: Validating an email. -->

$('#txtEmail').blur(function(e) {
var sEmail = $('#txtEmail').val();
if ($.trim(sEmail).length == 0) {
alert('Enter valid Email ID');
e.preventDefault();
}
var filter = /^([\w-.]+)@(([[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.)|(([\w-]+.)+))([a-zA-Z]
{2,4}|[0-9]{1,3})(]?)$/;
if (filter.test(sEmail)) {
alert('Valid Email');
}
else {
alert('Email not valid');
e.preventDefault();
}
});
<!-- HTML: Validating an email-->
<asp:TextBox id="txtEmail" runat="server" />
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