function subscribeToEmail()
{
    $("#emailSubscriptionErrorMsg").hide();
    var email = $("#subscriberEmail").val();
    if (!isValidEmail(email))
    {
        $("#emailSubscriptionErrorMsg").show('slow');
        return;
    }

    $("#emailSubscriptionErrorMsg").hide();
    $("#ajaxLoading").show();
    
    $.post("/Ajax/Email-Subscription.aspx", 
        {email: $("#subscriberEmail").val()},
        function(data)
        {
            // if return text contains "~", it signifies an error
            if (data == null || 
                data == "" ||
                data.indexOf("~") != -1)
            {
                return;
            }
                        
            $("#ajaxLoading").hide();
            $("#emailSubscriptionResponseContent").html(data).text();
            $("#emailSubscriptionResponseSection").show('slow');
        }
    );
}

function isValidEmail(email)
{
    return email.match(/^([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$/);
}