在typeScript中，我用angular进行了测试，结果还不错

deepCopy(obj) {


        var copy;

        // Handle the 3 simple types, and null or undefined
        if (null == obj || "object" != typeof obj) return obj;

        // Handle Date
        if (obj instanceof Date) {
            copy = new Date();
            copy.setTime(obj.getTime());
            return copy;
        }

        // Handle Array
        if (obj instanceof Array) {
            copy = [];
            for (var i = 0, len = obj.length; i < len; i++) {
                copy[i] = this.deepCopy(obj[i]);
            }
            return copy;
        }

        // Handle Object
        if (obj instanceof Object) {
            copy = {};
            for (var attr in obj) {
                if (obj.hasOwnProperty(attr)) copy[attr] = this.deepCopy(obj[attr]);
            }
            return copy;
        }

        throw new Error("Unable to copy obj! Its type isn't supported.");
    }

下面是deepCopy在TypeScript中的实现(代码中不包含任何内容):

const deepCopy = <T, U = T extends Array<infer V> ? V : never>(source: T ): T => {
  if (Array.isArray(source)) {
    return source.map(item => (deepCopy(item))) as T & U[]
  }
  if (source instanceof Date) {
    return new Date(source.getTime()) as T & Date
  }
  if (source && typeof source === 'object') {
    return (Object.getOwnPropertyNames(source) as (keyof T)[]).reduce<T>((o, prop) => {
      Object.defineProperty(o, prop, Object.getOwnPropertyDescriptor(source, prop)!)
      o[prop] = deepCopy(source[prop])
      return o
    }, Object.create(Object.getPrototypeOf(source)))
  }
  return source
}

我的看法是:

Object.assign(…)只复制属性，我们丢失了原型和方法。

Object.create(…)不是为我复制属性，只是创建一个原型。

对我有用的是使用Object.create(…)创建一个原型，并使用Object.assign(…)将属性复制到它:

因此对于对象foo，像这样进行克隆:

Object.assign(Object.create(foo), foo)

你可以在扩展语法中使用解构赋值:

var obj = {id = 1, name = 'product1'};
var clonedObject = {...obj};

我自己也遇到过这个问题，最后写了一个小库clone -ts，它提供了一个抽象类，它向任何扩展它的类添加了一个克隆方法。抽象类借用了芬顿接受的答案中描述的深度复制函数，只是替换了Copy = {};使用copy = object. create(originalObj)来保留原始对象的类。下面是一个使用该类的示例。

import {Cloneable, CloneableArgs} from 'cloneable-ts';

// Interface that will be used as named arguments to initialize and clone an object
interface PersonArgs {
    readonly name: string;
    readonly age: number;
}

// Cloneable abstract class initializes the object with super method and adds the clone method
// CloneableArgs interface ensures that all properties defined in the argument interface are defined in class
class Person extends Cloneable<TestArgs>  implements CloneableArgs<PersonArgs> {
    readonly name: string;
    readonly age: number;

    constructor(args: TestArgs) {
        super(args);
    }
}

const a = new Person({name: 'Alice', age: 28});
const b = a.clone({name: 'Bob'})
a.name // Alice
b.name // Bob
b.age // 28

或者你可以直接用克隆。克隆助手方法:

import {Cloneable} from 'cloneable-ts';

interface Person {
    readonly name: string;
    readonly age: number;
}

const a: Person = {name: 'Alice', age: 28};
const b = Cloneable.clone(a, {name: 'Bob'})
a.name // Alice
b.name // Bob
b.age // 28    

我尝试创建一个通用的复制/克隆服务，为嵌套对象保留类型。会爱反馈，如果我做错了什么，但它似乎工作到目前为止…

import { Injectable } from '@angular/core';

@Injectable()
export class CopyService {

  public deepCopy<T>(objectToClone: T): T {
    // If it's a simple type or null, just return it.
    if (typeof objectToClone === 'string' ||
      typeof objectToClone === 'number' ||
      typeof objectToClone === 'undefined' ||
      typeof objectToClone === 'symbol' ||
      typeof objectToClone === 'function' ||
      typeof objectToClone === 'boolean' ||
      objectToClone === null
    ) {
      return objectToClone;
    }

    // Otherwise, check if it has a constructor we can use to properly instantiate it...
    let ctor = Object.getPrototypeOf(objectToClone).constructor;
    if (ctor) {
      let clone = new ctor();

      // Once we've instantiated the correct type, assign the child properties with deep copies of the values
      Object.keys(objectToClone).forEach(key => {
        if (Array.isArray(objectToClone[key]))
          clone[key] = objectToClone[key].map(item => this.deepCopy(item));
        else
          clone[key] = this.deepCopy(objectToClone[key]);
      });

      if (JSON.stringify(objectToClone) !== JSON.stringify(clone))
        console.warn('object cloned, but doesnt match exactly...\nobject: ' + JSON.stringify(objectToClone) + "\nclone: " + JSON.stringify(clone))

      // return our cloned object...
      return clone;
    }
    else {
      //not sure this will ever get hit, but figured I'd have a catch call.
      console.log('deep copy found something it didnt know: ' + JSON.stringify(objectToClone));
      return objectToClone;
    }
  }
}