[编辑] 完整申请可在:http://bit.ly/1CGZzym
我收到错误:
Uncaught TypeError: Cannot set property '0' of undefined
使用以下代码。我相信这是因为我没有正确声明 2D 数组的子数组,但我真的很困惑应该在哪里声明它。任何想法都会很棒。
// Create an array for the tiles we're about to draw
var tileArray = []
在函数外部声明。
我认为这是因为我试图在每个 [col] 中创建子元素,所以我想我需要在某处声明每个 col 编号,但我尝试的任何操作似乎都不起作用。
function drawGrid()
{
// Draw diamond grid
var col = 0;
var row = 0;
topTileX = (viewWidth/2);
topTileY = 0;
var nextX = 0;
var nextY = 0;
var getCols = 0;
while (topTileX > -1)
{
tileArray[col][row] = new DiamondTile(topTileX, topTileY, tileWidth, true, col, row);
tileArray[col][row].draw();
while (tileArray[col][row].xPos + tileArray[col][row].tileWidth < (viewWidth) + tileWidth)
{
col++;
nextX = tileArray[col-1][row].xPos + tileArray[col-1][row].tileWidth / 2;
nextY = tileArray[col-1][row].yPos + tileArray[col-1][row].tileHeight / 2;
tileArray[col][row] = new DiamondTile(nextX, nextY, tileWidth, true, col, row);
tileArray[col][row].draw();
if (col == getCols)
{
break;
}
}
row++;
getCols = col;
col = 0;
topTileX = topTileX - tileWidth/2;
topTileY = topTileY + tileHeight/2;
}
};
为了演示目的,DiamondTile函数如下:
function DiamondTile(xPos,yPos,width,interactive,myCol,myRow)
{
// Set x and y position for this sprite
this.xPos = xPos;
this.yPos = yPos;
this.myRow = myRow;
this.myCol = myCol;
// Used for AI pathfinding
this.isObstacle = false;
this.isStart = false;
this.isEnd = false;
this.gValue = 0;
this.hValue = 0;
this.fCost = 0;
this.tileWidth = width;
this.tileHeight = this.tileWidth/2;
var self = this;
// Create sprite
this.spriteObj = new PIXI.Sprite(grass);
this.spriteObj.interactive = interactive;
this.spriteObj.anchor = new PIXI.Point(0.5,0);
this.spriteObj.hitArea = new PIXI.Polygon([
new PIXI.Point(0,0),
new PIXI.Point(100,50),
new PIXI.Point(0,100),
new PIXI.Point(-100,50)
]);
this.spriteObj.mouseover = function()
{
if (self.spriteObj.tint == 0xFFFFFF)
{
self.spriteObj.tint = 0xA7E846;
}
text2.setText(self.myCol + "," + self.myRow + " Start: " + self.isStart);
}
this.spriteObj.mouseout = function()
{
if (self.spriteObj.tint == 0xA7E846)
{
self.spriteObj.tint = 0xFFFFFF;
}
}
this.spriteObj.click = function()
{
if (startStage === true)
{
startStage = false;
self.isStart = true;
self.spriteObj.tint = 0x1AFF00;
text.setText("Now select an end point");
endStage = true;
return true;
}
if (endStage === true)
{
endStage = false;
self.isEnd = true;
self.spriteObj.tint = 0xFF0000;
text.setText("Now place some obstacles");
obsStage = true;
return true;
}
if (obsStage ===true)
{
self.isObstacle = true;
self.spriteObj.tint = 0x3B3B3B;
text.setText("Press 'C' to calculate path");
return true;
}
}
};
最佳答案
这是一个多维数组,您没有正确初始化第一维数组。在 while 循环中,您必须初始化第一个维度才能使用索引访问第二个维度元素:
while (topTileX > -1)
{
if (tileArray[col] == null)
tileArray[col] = [];
tileArray[col][row] = new DiamondTile(topTileX, topTileY, tileWidth, true, col, row);
tileArray[col][row].draw();
// omitted other code for brevity
}
Javascript 数组是动态的,在这种情况下初始化第一维数组元素就足够了。您不必初始化第二维中的各个项目。
更新:这是一个工作代码 http://jsfiddle.net/0qbq0fts/2/ 的 fiddle
此外,您的语义是错误的。按照书本,二维数组的第一维应该是行,第二维应该是列。
关于javascript - 2D Javascript 数组类型错误,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/28235300/