W3Schools 试用编辑器 - W3Schools 中文教程

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0"/>
<style>
canvas {
    border:1px solid #d3d3d3;
    background-color: #f1f1f1;
}
</style>
</head>
<body onload="startGame()">
<script>

var myGamePiece;

function startGame() {
    myGamePiece = new component(30, 30, "red", 10, 120);
    myGameArea.start();
}

function updateGameArea() {
    myGameArea.clear();
    myGamePiece.newPos();    
    myGamePiece.update();
}

function moveup() {
    myGamePiece.speedY -= 1; 
}

function movedown() {
    myGamePiece.speedY += 1; 
}

function moveleft() {
    myGamePiece.speedX -= 1; 
}

function moveright() {
    myGamePiece.speedX += 1; 
}
</script>
<div style="text-align:center;width:480px;">
  <button onclick="moveup()">UP</button><br><br>
  <button onclick="moveleft()">LEFT</button>
  <button onclick="moveright()">RIGHT</button><br><br>
  <button onclick="movedown()">DOWN</button>
</div>

<p>If you click a button the red square will start moving. Click the same button many times, and it will move faster and faster.</p>
</body>
</html>