flex 日期工具类

public static function stringToDate(date:String):Date{
return DateField.stringToDate(date,"YYYY-MM-DD");
}

private static var df:DateFormatter=new DateFormatter();
df.formatString="YYYY-MM-DD";
public static function addYear(date:String,year:Number):String{
var de:Date=stringToDate(date);
de.setFullYear(de.getFullYear()+year);
return df.format(de);
}
public static function addMonth(date:String,month:Number):String{
var de:Date=stringToDate(date);
de.setMonth(de.getMonth()+month);
return df.format(de);
}
public static function addDay(date:String,day:Number):String{
var de:Date=stringToDate(date);
de.setDate(de.getDate()+day);
return df.format(de);
}