浅拷贝和深拷贝

浅拷贝

  // 简单赋值运算:浅拷贝
        var arr  = [1,2,3,4]
        var newArr = arr;
        newArr.push(5)
        console.log(arr);

深拷贝

        var arr = [{name:"lisi"},{name:"wangwu"}]
        var newArr = [...arr]
        arr[0].name = 'react'
        console.log(newArr);