计算两个时间之间的天数、小时等

function GetDate(startTime, endTime, diffType) {
    //将xxxx-xx-xx的时间格式，转换为 xxxx/xx/xx的格式
    start_time = startTime.replace(/-/g, "/");
    end_time = endTime.replace(/-/g, "/");
    //将计算间隔类性字符转换为小写
    diff_type = diffType.toLowerCase();
    var sTime =new Date(start_time); //开始时间
    var eTime =new Date(end_time); //结束时间
    //作为除数的数字
    var timeType =1;
    switch (diff_type) {
        case"second":
            timeType =1000;
            break;
        case"minute":
            timeType =1000*60;
            break;
        case"hour":
            timeType =1000*3600;
            break;
        case"day":
            timeType =1000*3600*24;
            break;
        default:break;
    }
    return parseInt((eTime.getTime() - sTime.getTime()) / parseInt(timeType));
}
alert(GetDate("2018-09-14 00:00:00","2018-09-14 11:33:22","day"));