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我一直在嘗試使用HTML5和Javascript將簡單的迷宮遊戲放在一起。我可以成功地將HTML和CSS內容加載到頁面上，但無論我嘗試什麼，我都無法加載JS。它絕對保存爲.html文件，我只使用Sublime文本將它放在一起（但我不會認爲這會影響到它）。只是有點難倒了，所以我認爲這一定是我在代碼中遺漏的東西。我不確定我是否錯過了一些東西？Javascript未加載HTML
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title> Maze Game </title>
</head>
<style>
canvas {
border: 8px double navy;
background: white;
}
img {
display: none;
}
button {
padding: 3px;
}
</style>
<body>
<canvas id="canvas"> </canvas>
<img id="sprite" src="sprite.png">
<script>
//these define the global variables for the canvas and the drawing context
var canvas;
var context;
var x = 0;
var y = 0; //positioning of the sprite
var dx = 0;
var dy = 0; //momentum of the sprite at start
window.onload = function() {
//setting up the canvas
canvas = document.getElementById("canvas");
context = canvas.getContext("2d");
//Draws the maze background
drawMaze("maze.png", 268, 5);
//On key press, run the following function
window.onkeydown = processKey;
};
var x = 0;
var y = 0;
function drawMaze(mazeFile, Xstart, Ystart) {
//This loads the maze picture in
dx = 0;
dy = 0; //if the face is already moving, stop it
var imgMaze = new Image();
imgMaze.onLoad = function() {
canvas.width = imgMaze.width;
canvas.height = imgMaze.height;
//Draws the maze onto the canvas
context.drawImage(imgMaze, 0, 0);
//draws the sprite and positions
x = Xstart;
y = Ystart;
var imgSprite = document.getElementById("sprite");
context.drawImage(imgSprite, x, y);
context.stroke();
//sets a short timer for the next frame to be drawn in (10ms)
setTimeout("drawFrame()", 10);
};
imgMaze.src = mazeFile;
}
function processKey(e) { //e needs to be used for event handling
//stop the sprite if it's already moving - enables collision
var dx = 0;
var dy = 0;
//condition for the Up arrow being pressed
if (e.keyCode == 38) {
dy = -1;
}
//condition for the Left arrow being pressed
if (e.keyCode == 37) {
dx = -1;
}
//condition for the Down arrow being pressed
if (e.keyCode == 40) {
dy = 1;
}
//condition for the Right arrow being pressed
if (e.keyCode == 39) {
dx = 1;
}
}
function drawFrame() {
if (dx != 0 || dy != 0) {
context.beginPath();
context.fillStyle = "rgb(254,244,207)";
context.rect(x, y, 15, 15);
context.fill
x += dx;
y += dy;
if (checkForCollision()) {
(dx/y = 0)
x -= dx;
y -= dy;
dx = 0;
dy = 0;
}
//Now we can finally draw the sprite!
var imgSprite = document.getElementById("sprite");
context.drawImage(imgSprite, x, y);
if (y > (canvas.height - 17)) {
alert("Congratulations! You made it!");
return;
}
}
timer = setTimeout(drawFrame, 10);
}
var imageData = context.getImageData(0, 0, 100, 50);
var pixels = imageData.data;
for (var i = 0, n = pixels.length; i < n; i += 4) {
//This will get the data/values for one pixel
var red = pixels[i];
var green = pixels [i+1];
var blue = pixels [i+2];
var alpha = pixels [i+3];
//This will invert the colours
pixels[i] = 255 - red;
pixels[i+1] = 255 - green;
pixels[i+2] = 255 - blue;
}
context.putImageData(imageData, 0, 0);
function checkForCollision() {
var imgData = context.getImageData(x-1, y-1, 15+2, 15+2);
var pixels = imgData.data;
//Then we need to perform a check, same as above
for (var i = 0; n = pixels.length, i < n; i += 4) {
var red = pixels[i];
var green = pixels[i+1];
var blue = pixels[i+2];
var alpha = pixels[i+3];
//now check for the black pixels for a wall
if (red == 0 && green == 0 && blue == 0) {
return true;
} //checks for a greyish colour - possibly the edge of a wall
if (red == 169 && green == 169 && blue == 169) {
return true;
}
}
return false; //there was no collision
}
</script>
</body>
</html>
「我無法獲得JS加載」是什麼意思？控制檯中是否有任何錯誤（F12）？你有沒有做過任何基本的調試？ – Andy 2014-10-17 10:35:14
您是在本地運行代碼還是從服務器運行代碼？你正在使用哪種瀏覽器？開發人員工具中是否顯示任何錯誤？ – 2014-10-17 10:35:24
其實你有一個錯誤。第115行：ReferenceError：無效賦值左邊：表示「（dx/y = 0）」的行。 – Andy 2014-10-17 10:36:32