static

1.static —>静态变量或静态方法

1. 静态变量是不能被改变的
2. 静态方法是不能被重写的
3. 静态方法直接通过类名调用—>(方便调用)
4. 静态方法中不能调用非静态的方法

   <script>
     class Person{
         sayAge(){
             console.log(18)
         }
         static sayName(){
             this.sayAge()
             console.log("hello")
         }
     }
     var p = new Person();
     Person.sayName()
   </script>

   

2.static-extends

<srcipt>
   class person(){
     static request(){
       console.log("hello world")
     }
   }
   class student extends person{
     static getTop250(){
       this.request()
     }
   }
  </script>

2.1例子—请求网易云—华语

HTTP.js

var baseUrl="https://music.aityp.com/";
  class HTTP{
    static request({url,data}){
      return new Promise((resolve,reject)=>{
         wx.request({
           url:baseUrl+url,
           data,
           header:{'content-type':'aplication/json'},
           method:'GET',
           dataType:'json',
           responseType:'text',
           success:(res)=>{
             resolve(res)
           },
           fail:(err)=>{
             reject(err)
           }
         });  
      }
      module.exports=HTTP;

IndexModel.js

const HTTP=require('./HTTP')
class IndexModel extends HTTP{
  static getMusic(){
    return this.request({
      url:'top/playlist',
      data:{
        cat:"华语"
      }
    })
  }
}
module.expots=IndexModel;