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HomeWeb Front-endJS TutorialJavaScript implements simple three-level linkage between provinces and municipalities_javascript skills

When we register a website, we will see the three-level linkage between provinces and municipalities. Here is a brief introduction

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<html lang="en">
 <head>
 <meta charset="UTF-8">
 <meta name="Generator" content="EditPlus&reg;">
 <meta name="Author" content="">
 <meta name="Keywords" content="">
 <meta name="Description" content="">
 <title>Document</title>
 </head>
 <body>
<select id="province" onChange="ck()" >
    <option>--请选择--</option>
   </select>
   <select id="city"> 
    <option>--请选择--</option>
   </select>
   <select id="san">
    <option>--请选择--</option>
   </select>
 </body>
 <script type="text/javascript">
 //======================================第一种方法:获取省市二级联菜单=============================
 //获取省的id
 var prame= document.getElementById("province");
 var city= document.getElementById("city");
var san= document.getElementById("san");
 //创建省市数组
 var cityList=new Array();
   //创建另一个数组
  var zushu=new Array;
   cityList['江西省'] = ['南昌市','抚州市','上饶市','鹰潭市','丰城市','吉安市'];
   cityList['河南省'] = ['郑州市','洛阳市'];
   cityList['湖北省'] = ['武汉市','宜昌市'];
   cityList['福建省'] = ['福州市','三明市','佛山市'];
   zushu['南昌市']=['南昌县','青云谱区','莲塘镇'];
   zushu['抚州市']=['临川区','云山镇','唱凯镇'];
   for(var i in cityList){
    prame.add(new Option(i,i),null);
   }
    prame.onchange=function(){
    var prame= document.getElementById("province").value;
    var city= document.getElementById("city");
    
    city.options.length=0;
    for(var k in cityList[prame]){
       city.add(new Option(cityList[prame][k],cityList[prame][k]),null);
  }
 }
 city.onchange=function(){
   var city= document.getElementById("city").value;
    var san= document.getElementById("san");
    
    san.options.length=0;
    for(var k in zushu[city]){
       san.add(new Option(zushu[city][k]),(zushu[city][k]),null);
  }
 }
</script>
 <!--------------------------------第二种方法:三级联动菜单----------------------
 <script type="text/javascript">
 
        //获取省的id
     var province=document.getElementById("province");
       province.add(new Option("江西省","江西省"),null);
       province.add(new Option("福建省","福建省"),null);
      province.add(new Option("广东省","广东省"),null);
     function ck(){
        
       var city=document.getElementById("city");
        var num=province.selectedIndex;
        city.options.length=0;
  
    switch(num){
      case 1:
       city.add(new Option("南昌市","南昌市"),null);
       city.add(new Option("抚州市","抚州市"),null);
     city.add(new Option("上饶市","上饶市"),null);
       city.add(new Option("吉安市","吉安市"),null);
       break;
       
      case 2:
       city.add(new Option("厦门市","厦门市"),null);
       city.add(new Option("三明市","三明市"),null);
     city.add(new Option("莆田市","莆田市"),null);
       city.add(new Option("龙岩市","龙岩市"),null);
       break;
     
      case 3:
       city.add(new Option("广州市","广州市"),null);
       city.add(new Option("东莞市","东莞市"),null);
     city.add(new Option("保定市","保定市"),null);
       city.add(new Option("珠海市","珠海市"),null);
       break;
        } 
      
      var qu=document.getElementById("qu");
      var num1=province.selectedIndex;
      qu.options.length=0;
      switch(num1){
      case 1:
       qu.add(new Option("临川区","临川区"),null);
       qu.add(new Option("青云谱区","青云谱区"),null);
     qu.add(new Option("南昌镇","南昌镇"),null);
       qu.add(new Option("云山镇","云山镇"),null);
       break;
       
      case 2:
      qu.add(new Option("保安县","保安县"),null);
      qu.add(new Option("福田区","福田区"),null);
     qu.add(new Option("将乐县","将乐县"),null);
      qu.add(new Option("厦门区","厦门区"),null);
       break;
     
     case 3:
      qu.add(new Option("广上县","光上县"),null);
      qu.add(new Option("西莞区","西莞区"),null);
     qu.add(new Option("三海县","三海县"),null);
      qu.add(new Option("广岛区","广岛区"),null);
       break;
        } 
   } 
 </script>-->
</html>

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