Question

我想在此Board类中创建并填充两个三维数组，但是我的方法似乎不起作用。它只返回一个函数而不是一个值。我应该通过方法而不是在类构造函数中执行此操作吗？

class Board{
    constructor(width,height,cols,rows)
    {
        this.width=width;
        this.height=height;
        this.cols=cols;
        this.rows=rows;
        this.array= function(){
            let array=[];
            for(let i=0;i<this.cols;i++)
            {
                array[i]=[];
                for(let j=0;j<this.rows;j++){
                    array[i][j]=0;
                }
            }
            return array;
        }
    }

Answer 1

不需要内部函数，只需填充数组并将其分配给属性即可。

class Board {
  constructor(width, height, cols, rows) {
    this.width = width;
    this.height = height;
    this.cols = cols;
    this.rows = rows;
    let array = [];
    for (let i = 0; i < this.cols; i++) {
      array[i] = [];
      for (let j = 0; j < this.rows; j++) {
        array[i][j] = 0;
      }
    }
    this.array = array;
  }
}

const b = new Board(2, 3, 4, 5);
console.log(b.array);

Answer 2

可以更容易

class Board {
  constructor(width, height, cols, rows) {
    this.width = width;
    this.height = height;
    this.cols = cols;
    this.rows = rows;
    this.array = [];
    for (let i = 0; i < this.cols; i++) {
      this.array.push(new Array(this.rows).fill(0));
    }
  }

Answer 3

您可以直接将值放在属性上而无需运行

class Board {
  constructor(width, height, cols, rows) {
    this.width = width;
    this.height = height;
    this.cols = cols;
    this.rows = rows;
    let array = new Array(this.cols).fill(0).map(val=> new Array(this.rows).fill(0))
    this.array = array;
  }
}

const b = new Board(2, 3, 4, 5);
console.log(b.array);

Answer 4

this.array= function(){
    let array=[];
    for(let i=0;i<this.cols;i++)
    {
        array[i]=[];
        for(let j=0;j<this.rows;j++){
            array[i][j]=0;
        }
    }
    return array;
}

这只会创建一个名为this.array的函数。

如果您希望this.array保留返回值，请直接在其中调用该函数。

this.array= (function(){
    let array=[];
    for(let i=0;i<this.cols;i++)
    {
        array[i]=[];
        for(let j=0;j<this.rows;j++){
            array[i][j]=0;
        }
    }
    return array;
})();

如何在ES6类构造函数中创建和填充两个三维数组

4 个答案: