获取当前系统时间并格式化成年月日（例如：2015-05-05）

var day = new Date();
var Year = 0;
var Month = 0;
var Day = 0;
var CurrentDate = "";
Year    = day.getFullYear();//ie火狐下都可以
Month   = day.getMonth()+1;
Day     = day.getDate()-1;
					   
CurrentDate += Year + "-";
					   
if (Month >= 10 )
{
CurrentDate += Month + "-";
 }
else
 {
 CurrentDate += "0" + Month + "-";
 }
if (Day >= 10 )
 {
CurrentDate += Day ;
 }
else
{
CurrentDate += "0" + Day ;
}