匹配的日期格式為 ：yyyy-MM-dd hh:mm:ss
如：var time = ‘2016-02-17 13:13:45’;不是則返回false；

function check(time){
    var r = time.match(/^(\d{1,4})(-|\/)(\d{1,2})\2(\d{1,2}) (\d{1,2}):(\d{1,2}):(\d{1,2})$/);
    if(r==null)
        return false; 
    var d = new Date(r[1], r[3]-1,r[4],r[5],r[6],r[7]);
    return (d.getFullYear()==r[1
 
]&&(d.getMonth()+1)==r[3]&&d.getDate()==r[4]&&d.getHours()==r[5]&&d.getMinutes()==r[6]&&d.getSeconds()==r[7]);
}