js日期比较

//比较时间 格式 yyyy-mm-dd hh:mi:ss
function comptime(beginTime,endTime){
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);

// alert(beginTime+endTime+beginTime);
// alert(Date.parse(endTime));alert(Date.parse(beginTime));

var a =(Date.parse(endTime)-Date.parse(beginTime))/3600/1000;

if(a<0){
return -1;
}else if (a>0){
return 1;
}else if (a==0){
return 0;
}else{
return 'exception'
}


}