如何使用 Typescript 实现带有自定义方法的类似数组的类？

我想实现一个类似数组的类：

1. 接受数组作为构造函数的参数
2. 应该是可迭代的并且具有所有内置数组的方法
3. 有一些自定义方法
4. 应该能够扩展其他类

我是这样看的：

class BaseModel {
  arr: Array;

  constructor(arr: Array<any>) { // <= req. #1
    this.arr = arr;
  }

  serialize(arr) { // <= req. #3
    this.arr = arr;
  }
}

class ListModel extends BaseModel { // <= req. #4
  constructor(arr: Array<any>) { // <= req. #1
    super(arr);
  }

  sayHello() { // <= req. #3
    console.log('hello');
  }
}

let list = new ListModel([1,2,3]);
list.sayHello();
// expected output:
// 'hello'
list.push(4); // <= req. #2

for (let a of list) { // <= req. #2
  console.log(a);
}
// expected output:
// 1
// 2
// 3
// 4
list.serialize([2,3]);

for (let a of list) {
  console.log(a);
}
// expected output:
// 2
// 3

用打字稿可以吗？我寻找解决方案，但没有找到更接近这些要求的解决方案。谢谢！

您可以延长Array类并通过这样做建立要求＃2。
我认为这是一个符合您所有要求的实现：

class MyArray<T> extends Array<T> {
    constructor(items?: T[]) {
        super();
        items && this.addItems(items);
    }

    public serialize(items: T[]): void {
        this.splice(0, this.length);
        this.addItems(items);
    }

    private addItems(items: T[]) {
        items.forEach(item => this.push(item));
    }
}

class StringsList extends MyArray<string> {
    public sayHello(): void { // req. #3
        console.log("hello");
    }
}

class NumbersList extends MyArray<number> {
    public sum(): number { // req. #3
        return this.reduce((prev: number, current: number) => prev + current);
    }
}

如果您不喜欢泛型部分，您可以简单地扩展Array<any>.

Examples https://www.typescriptlang.org/play/#src=class%20MyArray%3CT%3E%20extends%20Array%3CT%3E%20%7B%0A%09constructor(items%3F%3A%20T%5B%5D)%20%7B%0A%09%09super()%3B%0A%09%09items%20%26%26%20this.addItems(items)%3B%0A%09%7D%0A%0A%09public%20serialize(items%3A%20T%5B%5D)%3A%20void%20%7B%0A%09%09this.splice(0%2C%20this.length)%3B%0A%09%09this.addItems(items)%3B%0A%09%7D%0A%0A%09private%20addItems(items%3A%20T%5B%5D)%20%7B%0A%09%09items.forEach(item%20%3D%3E%20this.push(item))%3B%0A%09%7D%0A%7D%0A%0Aclass%20StringsList%20extends%20MyArray%3Cstring%3E%20%7B%0A%09public%20sayHello()%3A%20void%20%7B%0A%09%09console.log(%22hello%22)%3B%0A%09%7D%0A%7D%0A%0Aclass%20NumbersList%20extends%20MyArray%3Cnumber%3E%20%7B%0A%09public%20sum()%3A%20number%20%7B%0A%09%09return%20this.reduce((prev%3A%20number%2C%20current%3A%20number)%20%3D%3E%20prev%20%2B%20current)%3B%0A%09%7D%0A%7D%0A%0Alet%20arr1%20%3D%20new%20MyArray(%5B%22hey%22%2C%204%2C%20true%5D)%3B%0Aconsole.log(arr1)%3B%20%2F%2F%20%5B%22hey%22%2C%204%2C%20true%5D%0A%0Aarr1.push(99)%3B%0Aconsole.log(arr1)%3B%20%2F%2F%20%5B%22hey%22%2C%204%2C%20true%2C%2099%5D%0A%0Aarr1.forEach(item%20%3D%3E%20console.log(item))%3B%20%2F%2F%20hey%2C%204%2C%20true%2C%2099%0A%0Alet%20arr2%20%3D%20new%20StringsList(%5B%22str1%22%2C%20%22str2%22%5D)%3B%0Aconsole.log(arr2)%3B%20%2F%2F%20%5B%22str1%22%2C%20%22str2%22%5D%0A%0Aarr2.serialize(%5B%22str3%22%2C%20%22str4%22%5D)%3B%0Aconsole.log(arr2)%3B%20%2F%2F%20%5B%22str3%22%2C%20%22str4%22%5D%0A%0Alet%20arr3%20%3D%20new%20NumbersList(%5B1%2C2%2C3%2C4%2C5%5D)%3B%0Aconsole.log(arr3.sum())%3B%20%2F%2F%2015:

let arr1 = new MyArray(["hey", 4, true]);
console.log(arr1); // ["hey", 4, true]

arr1.push(99);
console.log(arr1); // ["hey", 4, true, 99]

arr1.forEach(item => console.log(item)); // hey, 4, true, 99

let arr2 = new StringsList(["str1", "str2"]);
console.log(arr2); // ["str1", "str2"]

arr2.serialize(["str3", "str4"]);
console.log(arr2); // ["str3", "str4"]

let arr3 = new NumbersList([1,2,3,4,5]);
console.log(arr3.sum()); // 15