let obj = {

      name:'zhagnsan',

      age:30,

      school:'pinghai'

    }

  object.assign

    function copy(obj){

      return Object.assign({},obj)

    }

    console.log(copy(obj))

    ...展开运算符

    function copy2(obj){

      return {...obj}

    }

    console.log(copy2(obj))

    let a = {

      age:1,

      jobs:{first:'FE'}

    }

    let b = copy(a)

    a.jobs.first = 'native'

    console.log(b.jobs.first)

    console.log(a.jobs.first)

    //浅拷贝，当对象层级大于2级时候，原来的对象属性也被改变了

   深拷贝

    function copyDeep(obj){

      return JSON.parse(JSON.stringify(obj))

    }

    console.log(copyDeep(obj))

   messageChannel

    function structuralClone(){

      return new Promise(resolve =>{

        const{port1,port2} = new MessageChannel()

        port2.onmessage = ev => resolve(ev.data)

        port1.postMessage(obj)

      })

    }

    obj2 = structuralClone(obj)

    console.log(obj2)