Backend DevelopmentPHP TutorialAjax combined with php to implement secondary linkage instance methodAjax combined with php to implement secondary linkage instance method
This article mainly introduces Ajax combined with PHP to achieve secondary linkage in detail. It has certain reference value. Interested friends can refer to it. I hope it can help everyone.
Use ajax to get data from php
<!DOCTYPE html>
<html>
<head>
<title>Ajax案例一</title>
<meta charset="utf-8" />
</head>
<body>
<!-- 二级联动 -->
<select id="province">
<option>请选择</option>
<option>山东省</option>
<option>辽宁省</option>
<option>吉林省</option>
</select>
<select id="city">
<option>请选择</option>
</select>
<script>
// 1. 为<select>元素绑定onchange事件
var provinceEle = document.getElementById("province");
provinceEle.onchange = function(){
// 将id为city的元素内容清空
var city = document.getElementById("city");
var opts = city.getElementsByTagName("option");
for(var z=opts.length-1;z>0;z--){
city.removeChild(opts[z]);
}
// 2. 获取用户当前选择的省份名称
var province = provinceEle.value;
// 3. 创建对应的城市列表 - 数组
var cities = [];
switch (province){
case "山东省":
cities = ["青岛市","济南市","威海市","日照市","德州市"];
break;
case "吉林省":
cities = ["长春市","松原市","吉林市","通化市","四平市"];
break;
case "辽宁省":
cities = ["沈阳市","大连市","铁岭市","丹东市","锦州市"];
break;
}
// 遍历城市列表
for(var i=0;i<cities.length;i++){
// 4. 创建<option>元素
var option = document.createElement("option");
// 5. 将城市的信息添加到<option>元素上
var textNode = document.createTextNode(cities[i]);
option.appendChild(textNode);
// 6. 将创建的所有<option>元素添加到id为city元素上
city.appendChild(option);
}
}
</script>
</body>
</html>php:
<?php
// 用于处理客户端请求二级联动的数据
// 1. 接收客户端发送的省份信息
$province = $_POST['provcince'];
// 2. 判断当前的省份信息,提供不同的城市信息
switch ($province){
case '山东省':
echo '青岛市,济南市,威海市,日照市,德州市';
break;
case '辽宁省':
echo '沈阳市,大连市,铁岭市,丹东市,锦州市';
break;
case '吉林省':
echo '长春市,松原市,吉林市,通化市,四平市';
break;
}
// 服务器端响应的是字符串
?>Related recommendations:
vue select second-level linkage The second level defaults to selecting the first option value
js implementation in HTML Select secondary linkage instance sharing
jquery implements secondary linkage drop-down selection based on layui
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