zoukankan      html  css  js  c++  java
  • js对象深拷贝

    由于引用类型(数组、对象)是按地址传递,直接拷贝是浅拷贝,即修改拷贝后的变量,原变量也会改变。有时需要深拷贝一个对象,这时就需要遍历彻底复制,使原对象和拷贝对象完全脱离关系。

    代码:

        function deepCloneObj(obj){
            var i;
            var o = Array.isArray(obj) ? [] : {};
            for(i in obj){
                if(obj.hasOwnProperty(i)){
                    o[i] = typeof obj[i] === "Object"? deepCloneObj(obj[i]) : obj[i];
                }
            }
            return o;
        }

    实现细节:假定传入的是一个引用类型,首先判定传入的是数组还是对象,根据判定结果,确定o是初始化为空数组还是空对象。之后遍历传入引用类型的自有属性,并判定属性是否为对象,如果是的话做递归,否则直接复制给o。

    数组实例:

        var arr1 = ["sfsag","akghak","['fafa','gaag','rwet']",125];
        console.log(arr1);//["sfsag", "akghak", "['fafa','gaag','rwet']", 125]
        var arr2 = deepCloneObj(arr1);
        arr1.push("newstr");
        console.log(arr1);//["sfsag", "akghak", "['fafa','gaag','rwet']", 125, "newstr"]
        console.log(arr2);//["sfsag", "akghak", "['fafa','gaag','rwet']", 125]

    对象实例:

        var obj1 = {sgsh:{sfwg:'ssgsg'},asga:['aff','ghh','wegwer',12],segg:1};
        console.log(obj1);//Object {sgsh: Object, asga: Array[4], segg: 1}
        var obj2 = deepCloneObj(obj1);
        obj1['newstr'] = ['fsg','gsr'];
        console.log(obj1);//Object {sgsh: Object, asga: Array[4], segg: 1, newstr: Array[2]}
        console.log(obj2);//Object {sgsh: Object, asga: Array[4], segg: 1}
  • 相关阅读:
    web--ajax--json
    4.26
    4.25
    4.23
    4.22
    4.20
    4.19
    4.18
    4月问题总结章
    4.17
  • 原文地址:https://www.cnblogs.com/tisikcci/p/5879299.html
Copyright © 2011-2022 走看看