Javascript:我的画布什么也没画

Javascript:我的画布什么也没画,javascript,html5-canvas,Javascript,Html5 Canvas,我正在做一个基本的游戏循环,所以我从基本的立方体练习开始,我写了下面的例子,但它不起作用。我试着看看是否有拼错的地方,但我什么也找不到 <!DOCTYPE HTML> <html> <head> <title>Game</title> <style type="text/css"> #GameCanvas { background-color: #FF0000; } </style> </head&g

我正在做一个基本的游戏循环,所以我从基本的立方体练习开始,我写了下面的例子,但它不起作用。我试着看看是否有拼错的地方,但我什么也找不到

<!DOCTYPE HTML>
<html>
<head>
<title>Game</title>
<style type="text/css">
#GameCanvas {
   background-color: #FF0000;
}
</style>
</head>
<body>
<canvas id="GameCanvas" width="1000" height="600"></canvas>
<script type="text/javascript">
var canvas = document.findElementById("GameCanvas");
var graphics = canvas.getContext("2d");
function Update() {}
function Draw() {
graphics.beginPath();
graphics.fillRect(20, 20, 50, 50);
graphics.fillStyle = "#FFFFFF";
graphics.fill();
graphics.closePath();
}
function GameLoop() {
Update();
Draw();
requestAnimFrame(GameLoop);
}
requestAnimFrame(GameLoop);
</script>
</body>
</html>

游戏
#游戏画布{
背景色:#FF0000;
}
var canvas=document.findElementById(“GameCanvas”);
var graphics=canvas.getContext(“2d”);
函数更新(){}
函数绘图(){
graphics.beginPath();
graphics.fillRect(20,20,50,50);
graphics.fillStyle=“#ffffffff”;
graphics.fill();
graphics.closePath();
}
函数GameLoop(){
更新();
Draw();
请求帧(GameLoop);
}
请求帧(GameLoop);

这里有几个错误,
document.findElementById
不存在,请将其更改为
document.getElementById

在这两种情况下,
requestAnimationFrame
都应更改为
requestAnimationFrame

通过这些更改,循环运行并在屏幕上绘制一个正方形

<!DOCTYPE HTML>
<html>
<head>
<title>Game</title>
<style type="text/css">
#GameCanvas {
   background-color: #FF0000;
}
</style>
</head>
<body>
<canvas id="GameCanvas" width="1000" height="600"></canvas>
<script type="text/javascript">
var canvas = document.getElementById("GameCanvas");
var graphics = canvas.getContext("2d");
function Update() {}
function Draw() {
  graphics.beginPath();
  graphics.fillRect(20, 20, 50, 50);
  graphics.fillStyle = "#FFFFFF";
  graphics.fill();
  graphics.closePath();
}
function GameLoop() {
  Update();
  Draw();
  requestAnimationFrame(GameLoop);
}
requestAnimationFrame(GameLoop);
</script>
</body>
</html>

游戏
#游戏画布{
背景色:#FF0000;
}
var canvas=document.getElementById(“GameCanvas”);
var graphics=canvas.getContext(“2d”);
函数更新(){}
函数绘图(){
graphics.beginPath();
graphics.fillRect(20,20,50,50);
graphics.fillStyle=“#ffffffff”;
graphics.fill();
graphics.closePath();
}
函数GameLoop(){
更新();
Draw();
requestAnimationFrame(GameLoop);
}
requestAnimationFrame(GameLoop);

这里有几个错误,
document.findElementById
不存在,请将其更改为
document.getElementById

在这两种情况下,
requestAnimationFrame
都应更改为
requestAnimationFrame

通过这些更改,循环运行并在屏幕上绘制一个正方形

<!DOCTYPE HTML>
<html>
<head>
<title>Game</title>
<style type="text/css">
#GameCanvas {
   background-color: #FF0000;
}
</style>
</head>
<body>
<canvas id="GameCanvas" width="1000" height="600"></canvas>
<script type="text/javascript">
var canvas = document.getElementById("GameCanvas");
var graphics = canvas.getContext("2d");
function Update() {}
function Draw() {
  graphics.beginPath();
  graphics.fillRect(20, 20, 50, 50);
  graphics.fillStyle = "#FFFFFF";
  graphics.fill();
  graphics.closePath();
}
function GameLoop() {
  Update();
  Draw();
  requestAnimationFrame(GameLoop);
}
requestAnimationFrame(GameLoop);
</script>
</body>
</html>

游戏
#游戏画布{
背景色:#FF0000;
}
var canvas=document.getElementById(“GameCanvas”);
var graphics=canvas.getContext(“2d”);
函数更新(){}
函数绘图(){
graphics.beginPath();
graphics.fillRect(20,20,50,50);
graphics.fillStyle=“#ffffffff”;
graphics.fill();
graphics.closePath();
}
函数GameLoop(){
更新();
Draw();
requestAnimationFrame(GameLoop);
}
requestAnimationFrame(GameLoop);

您尝试过其他颜色吗?您尝试过其他颜色吗?