javascript - 功能未被识别为功能？

Question

我现在正处于深水中。不确定我知道我在做什么!无论如何，我正在尝试为我的贪吃蛇游戏制作一张 map 。目前我正在尝试添加一堵墙，但它不会工作!这是代码: https://editor.p5js.org/JensHaglof/sketches/YwtUO8992

或者写出来:

wallCount = 0
var walls = []
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
function setup() {
  createCanvas(400, 400);

  for (let i = 0; i < 20; i++){
    for (let j = 0 ; j < 20 ; j++){
      if (walls[i][j] == 1){
        walls[i][j] = new Wall(walls[i]*20, walls[j]*20);
        wallCount = wallCount + 1
      }
      }
}
}

function Wall(x, y){
  this.x = x;
  this.y = y;
  rect(this.x, this.y, 20, 20);

  this.display = function(){
  fill(255, 255, 0);
  rect(this.x, this.y, 20, 20);
  }
}

function draw() {

  background(0);
  for (let i = 0 ; i < wallCount ; i++){
    for (let j = 0 ; j < wallCount ; j++){
    walls[i][j].display();
  }
  }

}

我得到一个错误“TypeError: walls[i][j].display is not a function (sketch: line 52)”

我不知道从哪里开始。我正在尝试很多事情，但这就像我在黑暗中拍摄。任何人都知道怎么了？ /延斯

Answer 1

您只是初始化数组中 1 所在的位置，但您的代码期望整个二维数组包含 Wall 的实例。

在不理解你在做什么的情况下，你需要检查每个对象是否是墙的实例

if (walls[i][j] instanceof Wall) {
  walls[i][j].display();
}