ES6-Proxy，代理

let pro  = new Proxy({
    //方法体
    add:function(val){
        return val+100;
    },
    name:‘ananiah‘
},{
    //预处理机制 get set apply
    //get 得到属性前预处理
    get:function(target,key,property){
        console.log(target); //{add: ƒ, name: "ananiah"}
        console.log(key); //name
        return target[key]
    },
    set:function(target,key,value,receiver){
        console.log(`setting ${key} = ${value}`); //setting name = 代理

        //返回之后打印出来的才会改变
        return target[key] = value + ‘123‘;
    }
});
console.log(pro.name);
pro.name=‘代理‘;
console.log(pro.name);  //name 代理123

//apply
let target = function(){
     return  ‘ananiah‘;
}
let handler = {
    apply(target,ctx,args){
        console.log(‘apply start‘);
        return Reflect.apply(...arguments); //apply start
    }
};
let proxx = new Proxy(target,handler);
//调用
console.log(proxx()) //ananiah