es6(11)--Proxy,Reflect

 //Proxy,Reflect

 {
     let obj={
         time:'2018-06-25',
         name:'net',
         _r:123
     };
     let monitor = new Proxy(obj,{
         //拦截对象属性的读取
         get(target,key){
             return target[key].replace('2018','2019')
         },
         //拦截对象设置属性
         set(target,key,value){
             if(key==='name'){
                 return target[key]=value;
             }else{
                 return target[key];
             }
         },
         //拦截key in object 操作
         has(target,key){
             if(key==='name'){
                 return target[key];
             }else{
                 return false;
             }
         },
         //拦截delete
         deleteProperty(target,key){
             if(key.indexOf('_')>-1){
                 delete target[key];
                 return true;
             }else{
                 return target[key]
             }
         },
         //拦截Object.keys,Object.getOwnPropertySymbols,Object.getOwnPropertyNames
         ownKeys(target){
             return Object.keys(target).filter(item=>item!='time')
         }
     });
     console.log('get',monitor.time);
     monitor.name='web';
     console.log('set',monitor.name);
     console.log('has','name' in monitor);
     // delete monitor.time;
     // console.log('delete',monitor);
     // delete monitor._r;
     // console.log('delete',monitor);
      console.log('ownKeys',Object.keys(monitor));
 }
 {

     let obj={
         time:'2018-06-25',
         name:'net',
         _r:123
     };
     console.log('Reflect get',Reflect.get(obj,'time'))
     console.log('Reflect set',Reflect.set(obj,'time','2019-06-05'))
     console.log(obj);
     console.log('has',Reflect.has(obj,'name'))
 }
 //例子

 {
     function validator(target,validator){

         return new Proxy(target,{
             _validator:validator,
             set(target,key,value,proxy){
                 if(target.hasOwnProperty(key)){
                     let va=this._validator[key];
                     if(!!va(value)){
                         return Reflect.set(target,key,value,proxy)
                     }else{
                         throw Error(`不能设置${key}到${value}`)
                     }
                 }else{
                     throw Error(`${key} 不存在`)
                 }
             }
         })
     }
     const personValidators={
         name(val){
             return typeof val==='string'
         },
         age(val){
             return typeof val==='number'&&val>18
         }
     }
     class Person{
         constructor(name,age){
             this.age=age;
             this.name=name;
             return validator(this,personValidators)
         }
     }
     const person = new Person('lilei',30);
     console.info(person)
     person.name="qqq qq";
     console.info(person)
 }