兼容ie和firefox的日期函数---获取两个日期相差的天数

function TimeSpan(DateOne,DateTwo)//返回两个日期相差多少天，日期格式2008-8-8

{

var OneMonth = DateOne.substring(5,DateOne.lastIndexOf ('-'));

var OneDay = DateOne.substring(DateOne.length,DateOne.lastIndexOf ('-')+1);

var OneYear = DateOne.substring(0,DateOne.indexOf ('-'));

var TwoMonth = DateTwo.substring(5,DateTwo.lastIndexOf ('-'));

var TwoDay = DateTwo.substring(DateTwo.length,DateTwo.lastIndexOf ('-')+1);

var TwoYear = DateTwo.substring(0,DateTwo.indexOf ('-'));

var cha=((Date.parse(OneMonth+'/'+OneDay+'/'+OneYear)- Date.parse(TwoMonth+'/'+TwoDay+'/'+TwoYear))/86400000);

return Math.abs(cha);

}