JS

 JS日期比较(yyyy-mm-dd)

 function duibi(a, b) {
    var arr = a.split("-");
    var starttime = new Date(arr[0], arr[1], arr[2]);
    var starttimes = starttime.getTime();

    var arrs = b.split("-");
    var lktime = new Date(arrs[0], arrs[1], arrs[2]);
    var lktimes = lktime.getTime();

    if (starttimes >= lktimes) {
        alert('开始时间大于离开时间，请检查');
        return false;
    }
    else
        return true;
}

JS时间比较(yyyy-mm-dd hh:mi:ss)

function comptime() {
    var beginTime = "2009-09-21 00:00:00";
    var endTime = "2009-09-21 00:00:01";
    var beginTimes = beginTime.substring(0, 10).split('-');
    var endTimes = endTime.substring(0, 10).split('-');

    beginTime = beginTimes[1] + '-' + beginTimes[2] + '-' + beginTimes[0] + ' ' + beginTime.substring(10, 19);
    endTime = endTimes[1] + '-' + endTimes[2] + '-' + endTimes[0] + ' ' + endTime.substring(10, 19);

    var a = (Date.parse(endTime) - Date.parse(beginTime)) / 3600 / 1000;
    if (a < 0) {
        alert("endTime小!");
    } else if (a > 0) {
        alert("endTime大!");
    } else if (a == 0) {
        alert("时间相等!");
    } else {
        return 'exception'
    }
}