Typescript - 多维数组初始化 [英] Typescript - multidimensional array initialization

问题描述

我正在使用 Typescript，我想知道如何正确实例化和声明多维数组.这是我的代码:

I'm playing with Typescript and I wonder, how to properly instantiate and declare multidimensional array. Here's my code:

class Something {
    private things: Thing[][];

    constructor() {
        things = [][]; ??? how instantiate object ???

        for(var i: number = 0; i < 10; i++) {
            this.things[i] = new Thing[];   ??? how instantiate 1st level ???
            for(var j: number = 0; j< 10; j++) {
                this.things[i][j] = new Thing();   ??? how instantiate 2nd lvl item ???
            }
        }
    }
}

你能给我一些关于选定地点的提示吗?

Can you give me any hint about selected places?

推荐答案

您只需要 [] 来实例化一个数组 - 无论其类型如何，这都是正确的.数组是数组类型这一事实并不重要.

You only need [] to instantiate an array - this is true regardless of its type. The fact that the array is of an array type is immaterial.

同样的事情适用于循环的第一级.它只是一个数组，而 [] 是一个新的空数组 - 工作完成.

The same thing applies at the first level in your loop. It is merely an array and [] is a new empty array - job done.

至于第二层，如果 Thing 是一个类，那么 new Thing() 就可以了.否则，根据类型，您可能需要一个工厂函数或其他表达式来创建一个.

As for the second level, if Thing is a class then new Thing() will be just fine. Otherwise, depending on the type, you may need a factory function or other expression to create one.

class Something {
    private things: Thing[][];

    constructor() {
        this.things = [];

        for(var i: number = 0; i < 10; i++) {
            this.things[i] = [];
            for(var j: number = 0; j< 10; j++) {
                this.things[i][j] = new Thing();
            }
        }
    }
}

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