首页 > 代码库 > 关于时间的操作(JavaScript版)——年月日三级级联(默认依次显示请选择年、请选择月和请选择日)

关于时间的操作(JavaScript版)——年月日三级级联(默认依次显示请选择年、请选择月和请选择日)

        这篇博客和前一篇博客基本相同,只是显示的默认值不同:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
	<head>
		<title>年月日三级级联(默认依次显示请选择年、请选择月和请选择日)</title>
		<meta http-equiv="content-type" content="text/html; charset=UTF-8"/>
		<script type="text/javascript">
			function removeChilds(id){
				var childs = document.getElementById(id).childNodes;//这一行代码和紧跟的下面的for循环用于清除原来日的下拉列表的select中的对节点
				for(var i=childs.length-1;i>=0;i--) {
					document.getElementById(id).removeChild(childs[i]);      
				}
			}
			function setDay(){
				var yearToDate=document.getElementById("year").value;
				var monthToDate=document.getElementById("month").value;
				//alert(yearToDate+":"+monthToDate);
				var days=new Array(28,29,30,31);
				if(yearToDate==0||monthToDate==0){//如果是当前系统时间则设置默认的日
					var newOption = document.createElement("option");newOption.setAttribute("value",0);newOption.setAttribute("selected","selected");
					var textToNewOption=document.createTextNode("请选择日");newOption.appendChild(textToNewOption);
					document.getElementById("day").appendChild(newOption);
				}else{
					if(monthToDate==1||monthToDate==3||monthToDate==5||monthToDate==7||monthToDate==8||monthToDate==10||monthToDate==12){
						removeChilds("day");
						for( i=1; i<=days[3]; i++ ){
							var newOption = document.createElement("option");newOption.setAttribute("value",i);
							var textToNewOption=document.createTextNode(i);newOption.appendChild(textToNewOption);
							document.getElementById("day").appendChild(newOption);
						}
					}
					if(monthToDate==4||monthToDate==6||monthToDate==9||monthToDate==11){
						removeChilds("day");
						for( i=1; i<=days[2]; i++ ){
							var newOption = document.createElement("option");newOption.setAttribute("value",i);
							var textToNewOption=document.createTextNode(i);newOption.appendChild(textToNewOption);
							document.getElementById("day").appendChild(newOption);
						}
					}
					if(monthToDate==2){
						removeChilds("day");
						if(yearToDate%400==0||yearToDate%100!=0&&yearToDate%4==0){//闰年
							for( i=1; i<=days[1]; i++ ){
								var newOption = document.createElement("option");newOption.setAttribute("value",i);
								var textToNewOption=document.createTextNode(i);newOption.appendChild(textToNewOption);
								document.getElementById("day").appendChild(newOption);
							}
						}else{
							for( i=1; i<=days[0]; i++ ){
								var newOption = document.createElement("option");newOption.setAttribute("value",i);
								var textToNewOption=document.createTextNode(i);newOption.appendChild(textToNewOption);
								document.getElementById("day").appendChild(newOption);
							}
						}
					}	 
				}
			}
			function getMonth(){
				var m;
				document.write("<option value=http://www.mamicode.com/0 selected=/"selected/">请选择月");>