


js realizes the three-level linkage menu effect of provinces and municipalities
This article mainly shares the sample code of js to realize the effect of three-level linkage menu in provinces and municipalities. It has a very good reference value. Let’s take a look at it with the editor.
The effect is as follows:
Code As follows:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>省市区三级联动</title> </head> <body> <form> <select id="province"> <option>请选择省份</option> </select> <select id="city"> <option>请选择城市</option> </select> <select id="district"> <option>请选择区域</option> </select> </form> <script src="json.js"></script> <script type="text/javascript"> var proData = [], cityData = [], distData = []; var proSelect = document.getElementById("province"), citySelect = document.getElementById("city"), districtSelect = document.getElementById("district"); var curPro = "", curCity = ""; // 封装更新选择列表函数 function fillselect(select,list){ for (var i = select.length-1; i > 0 ; i--){ select.remove(i); } list.forEach(function(data){ var option = new Option(data.name, data.sheng); option.dataset.di = data.di; select.add(option); }) } // 将数据按省、市、地区分别存储 dataJson.forEach(function(data){ if (data.level === 1){ proData.push(data); } if (data.level === 2){ cityData.push(data); } if (data.level === 3){ distData.push(data); } }) fillselect(proSelect,proData); // 监听一级省份选择列表change事件,更新二级城市列表 proSelect.addEventListener("change",function(event){ var val = event.target.value; var list = []; cityData.forEach(function(d){ if (d.sheng === val) { list.push(d); } }) fillselect(citySelect,list); }) // 监听二级城市选择列表change事件,更新三级区域列表 citySelect.addEventListener("change",function(event){ var val = event.target.value; var curIndex = event.target.selectedIndex; curCity = event.target[curIndex].dataset.di; console.log(event.target,curCity); var list = []; distData.forEach(function(d){ if (d.di === curCity && d.sheng === val) { list.push(d); } }) fillselect(districtSelect,list); }) </script> </body> </html>
For more js to achieve the effect of three-level linkage menus in provinces and municipalities, please pay attention to the PHP Chinese website for related articles!
Related articles:
Use PHP to implement three-level linkage in urban areas with attached database
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Yii2 implementation example of three-level linkage between provinces and municipalities in China

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