如果你正在使用普通对象和数组，并且不关心克隆函数或递归引用，这里有一个简单的deepClone实现，它适用于普通对象、数组、字符串、数字、正则表达式、日期等。

// Simple Deep Clone
// Does not clone functions or handle recursive references.
function deepClone(original) {
  if (original instanceof RegExp) {
    return new RegExp(original);
  } else if (original instanceof Date) {
    return new Date(original.getTime());
  } else if (Array.isArray(original)) {
    return original.map(deepClone);
  } else if (typeof original === 'object' && original !== null) {
    const clone = {};
    Object.keys(original).forEach(k => {
      clone[k] = deepClone(original[k]);
    });
    return clone;
  }
  return original;
}

// Usage:

const obj = { n: 1, a: [ { a: 1 }, { a: 2 } ], d: new Date(), s: 'foo' };
const clone = deepClone(obj);

我很惊讶，客体。还没有提到Assign。

let cloned = Object.assign({}, source);

如果可用(例如Babel)，你可以使用对象展开操作符:

let cloned = { ... source };

在NodeJS中克隆Object的最简单和最快的方法是使用Object。Keys (obj)方法

var a = {"a": "a11", "b": "avc"};
var b;

for(var keys = Object.keys(a), l = keys.length; l; --l)
{
   b[ keys[l-1] ] = a[ keys[l-1] ];
}
b.a = 0;

console.log("a: " + JSON.stringify(a)); // LOG: a: {"a":"a11","b":"avc"} 
console.log("b: " + JSON.stringify(b)); // LOG: b: {"a":0,"b":"avc"}

方法Object。keys需要JavaScript 1.8.5;nodeJS v0.4.11支持此方法

当然对于嵌套对象需要实现递归func

另一个解决方案是使用原生JSON(在JavaScript 1.7中实现)，但它比之前的要慢得多(大约慢10倍)

var a = {"a": i, "b": i*i};
var b = JSON.parse(JSON.stringify(a));
b.a = 0;

关于这个问题的好文章:https://www.samanthaming.com/tidbits/70-3-ways-to-clone-objects/

var obj1 = {x: 5, y:5};
var obj2 = Object.assign({}, obj1 );
    
obj2  = {z: 10};
    
console.log(obj1);
console.log(obj2);

如果你正在使用普通对象和数组，并且不关心克隆函数或递归引用，这里有一个简单的deepClone实现，它适用于普通对象、数组、字符串、数字、正则表达式、日期等。

// Simple Deep Clone
// Does not clone functions or handle recursive references.
function deepClone(original) {
  if (original instanceof RegExp) {
    return new RegExp(original);
  } else if (original instanceof Date) {
    return new Date(original.getTime());
  } else if (Array.isArray(original)) {
    return original.map(deepClone);
  } else if (typeof original === 'object' && original !== null) {
    const clone = {};
    Object.keys(original).forEach(k => {
      clone[k] = deepClone(original[k]);
    });
    return clone;
  }
  return original;
}

// Usage:

const obj = { n: 1, a: [ { a: 1 }, { a: 2 } ], d: new Date(), s: 'foo' };
const clone = deepClone(obj);

There is no built-in way to do a real clone (deep copy) of an object in node.js. There are some tricky edge cases so you should definitely use a library for this. I wrote such a function for my simpleoo library. You can use the deepCopy function without using anything else from the library (which is quite small) if you don't need it. This function supports cloning multiple data types, including arrays, dates, and regular expressions, it supports recursive references, and it also works with objects whose constructor functions have required parameters.

代码如下:

//If Object.create isn't already defined, we just do the simple shim, without the second argument,
//since that's all we need here
var object_create = Object.create;
if (typeof object_create !== 'function') {
    object_create = function(o) {
        function F() {}
        F.prototype = o;
        return new F();
    };
}

/**
 * Deep copy an object (make copies of all its object properties, sub-properties, etc.)
 * An improved version of http://keithdevens.com/weblog/archive/2007/Jun/07/javascript.clone
 * that doesn't break if the constructor has required parameters
 * 
 * It also borrows some code from http://stackoverflow.com/a/11621004/560114
 */ 
function deepCopy = function deepCopy(src, /* INTERNAL */ _visited) {
    if(src == null || typeof(src) !== 'object'){
        return src;
    }

    // Initialize the visited objects array if needed
    // This is used to detect cyclic references
    if (_visited == undefined){
        _visited = [];
    }
    // Ensure src has not already been visited
    else {
        var i, len = _visited.length;
        for (i = 0; i < len; i++) {
            // If src was already visited, don't try to copy it, just return the reference
            if (src === _visited[i]) {
                return src;
            }
        }
    }

    // Add this object to the visited array
    _visited.push(src);

    //Honor native/custom clone methods
    if(typeof src.clone == 'function'){
        return src.clone(true);
    }

    //Special cases:
    //Array
    if (Object.prototype.toString.call(src) == '[object Array]') {
        //[].slice(0) would soft clone
        ret = src.slice();
        var i = ret.length;
        while (i--){
            ret[i] = deepCopy(ret[i], _visited);
        }
        return ret;
    }
    //Date
    if (src instanceof Date) {
        return new Date(src.getTime());
    }
    //RegExp
    if (src instanceof RegExp) {
        return new RegExp(src);
    }
    //DOM Element
    if (src.nodeType && typeof src.cloneNode == 'function') {
        return src.cloneNode(true);
    }

    //If we've reached here, we have a regular object, array, or function

    //make sure the returned object has the same prototype as the original
    var proto = (Object.getPrototypeOf ? Object.getPrototypeOf(src): src.__proto__);
    if (!proto) {
        proto = src.constructor.prototype; //this line would probably only be reached by very old browsers 
    }
    var ret = object_create(proto);

    for(var key in src){
        //Note: this does NOT preserve ES5 property attributes like 'writable', 'enumerable', etc.
        //For an example of how this could be modified to do so, see the singleMixin() function
        ret[key] = deepCopy(src[key], _visited);
    }
    return ret;
};