function DateDiff(interval, date1, date2) {
  var longl = date2.getTime() - date1.getTime(); //相差毫秒
	switch (interval.toLowerCase()) {
		case "y":
			return parseInt(date2.getFullYear() - date1.getFullYear());
		case "m":
			return parseInt((date2.getFullYear() - date1.getFullYear()) * 12 + (date2.getMonth() - date1.getMonth()));
		case "d":
			return parseInt(longl / 1000 / 60 / 60 / 24);
		case "w":
			return parseInt(longl / 1000 / 60 / 60 / 24 / 7);
		case "h":
			return parseInt(longl / 1000 / 60 / 60);
		case "n":
			return parseInt(longl / 1000 / 60);
		case "s":
			return parseInt(longl / 1000);
		case "l":
			return parseInt(longl);
	}
}

function getDateDiff(date1, date2) {
        var dic = {
            'd': '天前',
            'h': '小时前',
            'n': '分钟前',
            's': '刚刚'
        };
        for(var k in dic){
            var diff = DateDiff(k, date1, date2);
            if(diff){
                if(k == 's') {
                    return dic[k];
                }
                else if(k == 'd' && diff > 30) {
                    return Math.floor(diff/30) + '个月前';
                } else {
                    return diff + dic[k];
                }
            }
        }
}