JS实现简单省市二级联动

Z时代
2024-01-10
分类：综合

刚始学习java刚好看到用js实现省市二级联动的效果，就想着写篇博客，顺便检验下自己的学习成果。

好了废话少说先看看实际效果：

技术分析：

要实现这个功能呢，首先要用到html+js

这里用建一个下拉列表，绑定onchange事件


<select onchange="changeCity(this.value)">
 <option>--请选择--</option>
 <option value="0">湖北</option>
 <option value="1">湖南</option>
 <option value="2">河北</option>
 <option value="3">河南</option>
 </select>
 <select id="city">
</select>

好了下面是script部分了


<script>
 //1.创建一个二维数组用于存储省份和城市
 var cities = new Array(3);
 cities[0] = new Array("武汉市","黄冈市","襄阳市","荆州市");
 cities[1] = new Array("长沙市","郴州市","株洲市","岳阳市");
 cities[2] = new Array("石家庄市","邯郸市","廊坊市","保定市");
 cities[3] = new Array("郑州市","洛阳市","开封市","安阳市");
 function changeCity(val){
 //7.获取第二个下拉列表
 var c=document.getElementById("city");
 //9.清空第二个下拉列表的option内容
 c.options.length=0;
 //2.遍历二维数组中的省份
 for(var i=0;i<cities.length;i++){
 //注意，比较的是角标
 if(val==i){
 //3.遍历用户选择的省份下的城市
 for(var j=0;j<cities[i].length;j++){
 //alert(cities[i][j]);
 //4.创建城市的文本节点
 var a = document.createTextNode(cities[i][j]);
 //5.创建option元素节点
 var b = document.createElement("option");
 //6.将城市的文本节点添加到option元素节点
 b.appendChild(a);
 //8.将option元素节点添加到第二个下拉列表中去
 c.appendChild(b);
 }
 }
 }
 }
</script>

这样这个简单的省市二级联动就完成了，是不是特别简单呢？本人因为偷懒所以只写了四个省市，如果想完善点可以自己添加省市哦。

小编再为大家分享一位网友分享的一段代码：原生js实现省市二级联动，再此谢谢作者的分享。

通过document.createElement()创建option选项，再遍历数组appendChild到select对象内，三级联动就是用三位数组和嵌套遍历来实现。


<!DOCTYPE html>
<html>
 <head>
 <meta charset="UTF-8">
 <title>js省市二级联动</title>
 </head>
 <body>
 <form name="aform" method="get" action="#">
 省份：<select id="province" name="province" onchange="changeProvince(this.selectedIndex)"></select>
 城市：<select id="city" name="city"></select>
 </form>
 </body>
</html>
<script type="text/javascript">
 var provinces=["请选择省份","北京市","天津市","上海市","重庆市","江苏省","浙江省","江西省","海南省"];
 var citys=[
 ["请选择城市"],
 ["北京市"],
 ["天津市"],
 ["上海市"],
 ["重庆市"],
 ["南京市","无锡市","徐州市","常州市","苏州市","南通市","连云港市","淮安市","盐城市","扬州市","镇江市","泰州市","宿迁市"],
 ["杭州市","宁波市","温州市","绍兴市","湖州市","嘉兴市","金华市","衢州市","台州市","丽水市","舟山"],
 ["南昌市","九江市","上饶市","抚州市","宜春市","吉安市","赣州市","景德镇","萍乡市","新余市","鹰潭市"],
 ["海口市","三亚市","三沙市","儋州市"]
 ];
 window.onload=function(){
 var province=document.getElementById("province");
 var city=document.getElementById("city");
 var index=0;
 //创建好后加入到列表中
 for(var i in provinces)
 {
 var option = document.createElement("option");
 option.text=provinces[i];
 option.value=provinces[i];
 province.appendChild(option);
 }
 var option = document.createElement("option");
 option.text=citys[index];
 option.value=citys[index];
 city.appendChild(option);
 }
 function changeProvince(selectedIndex){
 var city=document.getElementById("city");
 city.options.length=0;
 for(var i in citys[selectedIndex])
 {
 var option = document.createElement("option");
 option.text=citys[selectedIndex][i];
 option.value=citys[selectedIndex][i];
 city.appendChild(option);
 }
 }
</script>