es6 语法 （Proxy和Reflect 的对比）

{ //原始对象 let obj={ time:'2017-03-11', name:'net', _r:123 }; //（代理商）第一个参数代理对象，第二个参数真正代理的东西 let monitor=new Proxy(obj,{ // 拦截对象属性的读取 get(target,key){ return target[key].replace('2017','2018') }, // 拦截对象设置属性 set(target,key,value){ if(key==='name'){ //赋值并返回 return target[key]=value; }else{ //不做操作直接返回 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); //2018-03-11 //操作 monitor.time='2018'; monitor.name='mukewang'; console.log('set',monitor.time,monitor);//2018-03-11;{time: "2017-03-11", name: "mukewang", _r: 123} console.log('has','name' in monitor,'time' in monitor);//true;false delete monitor.time; console.log('delete',monitor);//{time: "2017-03-11", name: "mukewang", _r: 123} // delete monitor._r; console.log('delete',monitor);//{time: "2017-03-11", name: "mukewang"} console.log('ownKeys',Object.keys(monitor));//["name", "_r"] } { let obj={ time:'2017-03-11', name:'net', _r:123 }; console.log('Reflect get',Reflect.get(obj,'time'));//get 2017-03-11 Reflect.set(obj,'name','mukewang'); console.log(obj);//{time: "2017-03-11", name: "mukewang", _r: 123} console.log('has',Reflect.has(obj,'name'));//true }

 

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