目前是否遵守夏令时
function isDaylightSavings(d:Date):Boolean {
    var months:uint = 12;
    var offset:uint = d.timezoneOffset;
    var offsetCheck:Number;
    while (months--) {
        offsetCheck = (new Date(d.getFullYear(), months, 1)).timezoneOffset;
        if (offsetCheck != offset)
            return (offsetCheck > offset);
    }
    return false;
}