原生JS封装深拷贝函数

封装一个深拷贝的函数

function DeepCopy(newObj, oldObj) {
    for(let key in oldObj) {
        //判定属性值的类型
        let item = oldObj[key]
        if(item instanceof Array) {   //如果属性值为数组
            newObj[key] = []
            DeepCopy(newObj[key], item)
        } else if(item instanceof Object) {  //属性值为对象
            newObj[key] = {}
            DeepCopy(newObj[key], item)
        } else {    //基本数据类型
            newObj[key] = item
         }
     }
}

实例：

let old = {
      name: 'james',
      age: 35,
      now: {
         team: 'lakers'
      },
      play: ['骑士', '热火', '湖人']
}
let new1 = {}
DeepCopy(new1, old)
console.log(new1)

/*  打印出
>{name: "james", age: 35, now: {…}, play: Array(3)}
age: 35
name: "james"
now: {team: "lakers"}
play: (3) ["骑士", "热火", "湖人"]
__proto__: Object
*/