本文实例为大家分享了JavaScript实现省市联动的具体代码，供大家参考，具体内容如下
实现效果：
1.当点击文字时选中对应的下拉菜单
2.选择省，后面跟本省对应的市
实现过程：
1.获得省的Dom对象
2.用循环为省的下拉菜单设置option子节点，并将数组每个pName的值赋给创建的子节点
3.每次循环同时为option子节点设置value属性
4.同理在点击省的同时，为市创建option子节点，并将cName的值赋给子节点，设置属性
实现细节：
1. 点击省时采用onchange事件（元素值改变时触发）
2. 每次为市增加节点，要将节点清空，否则市的节点会叠加，可采用option长度为0， citySel.options.length = 0;
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box{
width: 500px;
padding: 20px;
border: 1px solid #aaa;
margin: 100px auto;
}
.box select{
width: 150px;
margin: 10px;
}
</style>
<script>
var provs = [{"id":"01","pName":"河南省"},{"id":"02","pName":"河北省"},{"id":"03","pName":"四川省"}];
var citys = [{"id":"001","cName":"安阳市","pId":"01"},{"id":"002","cName":"郑州市","pId":"01"},{"id":"003","cName":"新乡市","pId":"01"},{"id":"004","cName":"邯郸市","pId":"02"},{"id":"005","cName":"石家庄市","pId":"02"},{"id":"006","cName":"合肥市","pId":"02"},{"id":"007","cName":"广陵市","pId":"03"},{"id":"008","cName":"成都市","pId":"03"},{"id":"009","cName":"重庆市","pId":"03"}];
function $(id){
return document.getElementById(id);
}
window.onload = function (){
var proSel = $('province');
for(var i = 0; i<provs.length; i++){
var Coption = document.createElement('option');
Coption.innerHTML = provs[i].pName;
Coption.setAttribute('value',provs[i].id);
proSel.appendChild(Coption);
}
proSel.onchange = function(){
var city =$('city');
var Pid = this.value;
city.options.length = 0;//把Select的属性清空
for(var i=0; i<citys.length; i++){
if(Pid == citys[i].pId){
var Noption = document.createElement('option');
Noption.innerHTML = citys[i].cName;
Noption.setAttribute('value',citys[i].id);
city.appendChild(Noption);
}
}
}
}
</script>
</head>
<body>
<div class="box">
请选择：
<select id="province">
<option value="00">----请选择----</option>
</select><label for="province">省</label>
<select id="city">
<option value="000">----请选择----</option>
</select><label for="city">市</label>
</div>
</body>
</html>
