JS計算日期差

function Computation(sDate1,sDate2){
    var aDate, oDate1, oDate2, iDays;  
    aDate = sDate1.split("-");  
    oDate1 = new Date(aDate[0],aDate[1]-1,aDate[2]);  
    aDate = sDate2.split("-");  
    oDate2 = new Date(aDate[0],aDate[1]-1,aDate[2]);  
    
    iDays = parseInt(Math.abs(oDate1 - oDate2) / 1000 / 60 / 60 /24);    
    alert(iDays);
}