当在shtml页面中使用regex和jquery验证电子邮件文本框时，错误弹出，显示regex有问题，因为它在regex中包含“@”。

$(document).ready(function() {

$('#btn-submit').click(function() { 

    $(".error").hide();
    var hasError = false;
    var emailReg = /^([\w-\.]+@([\w-]+\.)+[\w-]{2,4})?$/;   //"@" in regex is the issue

    var emailaddressVal = $("#UserEmail").val();
    if(emailaddressVal == '') {
        $("#UserEmail").after('<span class="error">Enter email address.</span>');
        hasError = true;
    }

    else if(!emailReg.test(emailaddressVal)) {
        $("#UserEmail").after('<span class="error">Enter a valid email address.</span>');
        hasError = true;
    }

    if(hasError == true) { return false; }

   });
});