JavaScript深度克隆

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/** * 方法一 在Object.prototype中添加clone(); * RegExp 类型的对象调用JSON.stringify() 只会打印一个{} */Object.prototype.clone = function () {    if (this === null || !(typeof this === "object")) {        return this;    } else if (Object.prototype.toString.call(this).slice(8, -1) === "Date") {        return new Date(this.getTime());    } else if (Object.prototype.toString.call(this).slice(8, -1) === "RegExp") {        var pattern = this.valueOf();        var flags = '';        flags += pattern.global ? 'g' : '';        flags += pattern.ignoreCase ? 'i' : '';        flags += pattern.multiline ? 'm' : '';        return new RegExp(pattern.source, flags);    }    var o = Array.isArray(this) ? [] : {};    for (var attr in this) {        if (typeof this[attr] == "object") {            o[attr] = this[attr].clone();            continue;        }        o[attr] = this[attr]    }    return o;};/* test ---------------------------------------------------------- */var obj = {    a: 3,    b: "p",    c: false,    d: function (e) {        console.log(e);    },    e: undefined,    arr: [1, 3, {        a: 1,        b: "2",        arr: [1, new Date(),/[^\d]/g , 3]    }]};var object = obj.clone();object.arr[2].arr[0] = 4;console.log(obj.arr[2].arr[0]);console.dir(object)console.log(JSON.stringify(obj));console.log(JSON.stringify(object));


/** * 或者定义一个copy(); * 事实证明 JavaScript的类型自动转换能力真的很强将所有基本类型都包装了 instanceof Object is true (坑爹). */function copy(obj) {    if (obj === null || !(typeof obj === "object")) {        return obj;    } else if (Object.prototype.toString.call(obj).slice(8, -1) === "Date") {        return new Date(obj.getTime());    } else if (Object.prototype.toString.call(obj).slice(8, -1) === "RegExp") {        var pattern = obj.valueOf();        var flags = '';        flags += pattern.global ? 'g' : '';        flags += pattern.ignoreCase ? 'i' : '';        flags += pattern.multiline ? 'm' : '';        return new RegExp(pattern.source, flags);    }    // var o = isArray(obj) ? [] : {};    var o = Array.isArray(obj) ? [] : {};    for (var attr in obj) {        if (typeof obj[attr] == "object") {            o[attr] = copy(obj[attr]);        } else {            o[attr] = obj[attr];        }    }    return o;}/* test ---------------------------------------------------------- */var obj = {    a: 3,    b: "p",    c: false,    d: function (e) {        console.log(e);    },    arr: [1, 3, {        a: 1,        b: "2",        arr: [1, 2, 3, {            a: "c",            arr: ["8", 1],        }]    }]};console.log(copy(null));console.log(copy(4));var o = copy(obj);o.arr[2].arr[2] = 100;console.log(JSON.stringify(obj));console.log(JSON.stringify(o));/* 附Array.isArray的具体实现方法! ECMAScript5已经实现! 为什么不用instanceof? 因为很多时候instanceof不可靠 比如对象所在Windows不同时! */function isArray(obj) {    return typeof obj === "object" && Object.prototype.toString.call(obj).slice(8, -1) === "Array";};

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