javascript日期相减天数

var s1 = new Date(date1.replace(/-/g, "/"));
var s2 = new Date(date2.replace(/-/g, "/"));
var days = s1.getTime() - s2.getTime();
var time = parseInt(days / (1000 * 60 * 60 * 24));

//下面是计算比例的1/天数，可以忽略
if(time<0){
for(var i=1;i<=5;i++){
$dp.$('row'+num+''+i).innerHTML='';
}
}else{
for(var i=1;i<=time;i++){
$dp.$('row'+num+''+i).innerHTML=((1/time).toFixed(2))*100 +'%';
}
}