function YYYYMMDDstart(str,ymd,year,month,day,agoyears,afteryears){
    if(agoyears == "") agoyears = 30;
    if(afteryears == "") afteryears = 50;
	if(str == ""){
		//str =  new Date().getFullYear() + '-' + new Date().getMonth() + '-' + new Date().getDate();    
		//valuestr = str.split("-"); 
		//valuestr[1] = parseInt(valuestr[1])+1; 
		ymd.value = '';
	}else{
		ymd.value = str;
		valuestr = str.split("-"); 
	}

	MonHead = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
	//先给年下拉框赋内容
	var y = new Date().getFullYear();
	for (var i = (y+agoyears); i > (y-afteryears); i--) //以今年为准，前30年，后30年
		year.options.add(new Option(i,i));
		//赋月份的下拉框
	for (var i = 1; i < 13; i++)       
		month.options.add(new Option(i, i));
		if(valuestr[0] == "" || valuestr[0] == 'undefined'){
			year.value = y;
		}else{
			year.value = valuestr[0]; 
		}

	if(valuestr[1] == "" || valuestr[1] == 'undefined'){
		month.value = new Date().getMonth() + 1;
	}else{
	  
		var _tempvalue = valuestr[1];
		var str = _tempvalue.indexOf("0");
		if(str == 0) {
			mymonth = _tempvalue.substr(1, 1);
		} else {
			mymonth = _tempvalue;
		}

		month.value = parseInt(mymonth); 
	}

	//month.value = new Date().getMonth() + 1;
	var n = MonHead[new Date().getMonth()];
	if (new Date().getMonth() ==1 && IsPinYear(year.options[year.selectedIndex].value)) n++;
	writeDay(n,day); //赋日期下拉框Author:meizz
	if(valuestr[2] == "" || valuestr[0] == 'undefined'){
		day.value = new Date().getDate();
	}else{
		day.value = parseInt(valuestr[2].replace(/^0/, '')); 
	}
}

//年发生变化时日期发生变化(主要是判断闰平年)
function YYYYDD(str,ymd,month,day) {
	ymd.value = '';
	var MMvalue = month.options[month.selectedIndex].value;
	if (MMvalue == "" ){ var e = day; optionsClear(e); return;}
	var n = MonHead[MMvalue - 1];
	if (MMvalue ==2 && IsPinYear(str)) n++;
	writeDay(n,day);
	
	var MMvalue = month.options[month.selectedIndex].value;
	var DDvalue = day.options[day.selectedIndex].value;
	//alert(MMvalue);
	if(str != '' && MMvalue!= '' && DDvalue!= ''){
	ymd.value = str + '-' + MMvalue + '-' + DDvalue;
	}else{
	ymd.value = '';
	}
	
}
//月发生变化时日期联动
function MMDD(str,ymd,year,day){
	ymd.value = '';
	var YYYYvalue = year.options[year.selectedIndex].value;
	if (YYYYvalue == "" ){ var e = day; optionsClear(e); return;}
	 var n = MonHead[str - 1];
	if (str ==2 && IsPinYear(YYYYvalue)) n++;
	writeDay(n,day);

  var e = day;
 day.remove(0);
  
	var YYvalue = year.options[year.selectedIndex].value;
	var DDvalue = day.options[day.selectedIndex].value;
	

	if(YYvalue != '' && str != '' && DDvalue!= ''){
	ymd.value = YYvalue + '-' + str + '-' + DDvalue;
	}else{
	ymd.value = '';
	}

	
}
//日发生变化时日期文本框改变
function DD(str,ymd,year,month,day){
	var YYvalue = year.options[year.selectedIndex].value;
	var MMvalue = month.options[month.selectedIndex].value;
	if(YYvalue != '' && MMvalue!= '' && str!= ''){
	ymd.value = YYvalue + '-' + MMvalue + '-' + str;
	}else{
	ymd.value = '';
	}
}

//据条件写日期的下拉框
function writeDay(n,day){
	var e = day; optionsClear(e);
	for (var i=1; i<(n+1); i++){
		e.options.add(new Option(i,i));
	}
}
//判断是否闰年
function IsPinYear(year){ 
	return(0 == year%4 && (year%100 !=0 || year%400 == 0));
}
function optionsClear(e){
	for (var i=e.options.length; i>0; i--)
	e.remove(i);
}