mirror of
https://github.com/Daotin/Web.git
synced 2024-11-01 13:34:47 +08:00
133 lines
3.9 KiB
Markdown
133 lines
3.9 KiB
Markdown
|
省市联动案例:
|
|||
|
|
|||
|
```html
|
|||
|
<!DOCTYPE html>
|
|||
|
<html lang="en">
|
|||
|
|
|||
|
<head>
|
|||
|
<meta charset="UTF-8">
|
|||
|
<meta name="viewport" content="width=device-width, initial-scale=1.0">
|
|||
|
<meta http-equiv="X-UA-Compatible" content="ie=edge">
|
|||
|
<title>Document</title>
|
|||
|
</head>
|
|||
|
|
|||
|
<body>
|
|||
|
<select name="" id="province">
|
|||
|
<option value="">请选择省份</option>
|
|||
|
</select>
|
|||
|
|
|||
|
<select name="" id="city">
|
|||
|
<option value="">请选择市</option>
|
|||
|
</select>
|
|||
|
|
|||
|
<select name="" id="area">
|
|||
|
<option value="">请选择区</option>
|
|||
|
</select>
|
|||
|
</body>
|
|||
|
<script>
|
|||
|
var province = document.querySelector("#province");
|
|||
|
var city = document.querySelector("#city");
|
|||
|
var area = document.querySelector("#area");
|
|||
|
|
|||
|
var xhr = new XMLHttpRequest();
|
|||
|
xhr.open("get", "http://api.yytianqi.com/citylist/id/2", true);
|
|||
|
xhr.send();
|
|||
|
xhr.onreadystatechange = function () {
|
|||
|
if (this.readyState == 4 && this.status == 200) {
|
|||
|
var json = JSON.parse(this.responseText);
|
|||
|
var jsonList = json.list;
|
|||
|
var provinceHtml = "<option value=''>请选择省份</option>";
|
|||
|
|
|||
|
|
|||
|
jsonList.map(function (item) {
|
|||
|
var provinceId = item["city_id"];
|
|||
|
var provinceName = item["name"];
|
|||
|
provinceHtml += `<option value="${provinceId}">${provinceName}</option>`;
|
|||
|
});
|
|||
|
|
|||
|
province.innerHTML = provinceHtml;
|
|||
|
|
|||
|
// 当province的 select 里面value的值改变的时候
|
|||
|
var cityList = [];
|
|||
|
province.onchange = function () {
|
|||
|
var provinceId = this.value; // 省的id
|
|||
|
var province = jsonList.filter(function (item) {
|
|||
|
return item["city_id"] == provinceId;
|
|||
|
})[0];
|
|||
|
cityList = province.list;
|
|||
|
|
|||
|
var cityHtml = '<option value="">请选择市</option>';
|
|||
|
cityList.map(function (item) {
|
|||
|
var cityId = item["city_id"];
|
|||
|
var cityName = item["name"];
|
|||
|
cityHtml += `<option value=${cityId}>${cityName}</option>`
|
|||
|
});
|
|||
|
city.innerHTML = cityHtml;
|
|||
|
};
|
|||
|
|
|||
|
// 当city的select 里面value的值改变的时候
|
|||
|
city.onchange = function () {
|
|||
|
var cityId = this.value;
|
|||
|
|
|||
|
var city = cityList.filter(function (item) {
|
|||
|
return item["city_id"] == cityId;
|
|||
|
})[0];
|
|||
|
|
|||
|
|
|||
|
var areaList = city.list;
|
|||
|
// 判断是否为直辖市
|
|||
|
if (areaList) {
|
|||
|
area.style.display = "inline-block";
|
|||
|
var areaHtml = '<option value="">请选择区</option>';
|
|||
|
areaList.map(function (item) {
|
|||
|
var areaId = item["city_id"];
|
|||
|
var areaName = item["name"];
|
|||
|
areaHtml += `<option value="${areaId}">${areaName}</option>`;
|
|||
|
});
|
|||
|
area.innerHTML = areaHtml;
|
|||
|
} else {
|
|||
|
area.style.display = "none";
|
|||
|
}
|
|||
|
};
|
|||
|
}
|
|||
|
};
|
|||
|
</script>
|
|||
|
|
|||
|
</html>
|
|||
|
```
|
|||
|
|
|||
|
![](images/1.gif)
|
|||
|
|
|||
|
|
|||
|
|
|||
|
注意事项:
|
|||
|
|
|||
|
> Ajax最好不要用全局变量,因为Ajax请求需要时间,你获取到的可能是未更新的值。
|
|||
|
>
|
|||
|
> 如果非要使用的话,使用回调函数来执行这个变量。
|
|||
|
|
|||
|
```js
|
|||
|
var global = "";
|
|||
|
|
|||
|
var xhr = new XMLHttpRequest();
|
|||
|
xhr.open("get", "./data", true);
|
|||
|
xhr.send();
|
|||
|
xhr.onreadystatechange = function () {
|
|||
|
if (this.readyState == 4 && this.status == 200) {
|
|||
|
global = this.responseText;
|
|||
|
show(global);
|
|||
|
}
|
|||
|
};
|
|||
|
|
|||
|
function show(data) {
|
|||
|
alert(data);
|
|||
|
}
|
|||
|
```
|
|||
|
|
|||
|
|
|||
|
|
|||
|
上面省市联动中,在获取地区的列表时,需要用到市的信息,所以我们将市的列表提升出来:
|
|||
|
|
|||
|
`var cityList = [];`
|
|||
|
|
|||
|
由于这里 cityList 并不是在Ajax中获取的数据,所以没有这个考虑。但是上面的坑是一定要注意的。
|