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drag-html

<!doctype html>
<html>
<head>
<meta charset="UTF-8" />
<title>Canvas Drag and Drop Test</title>
</head>
<body>
<section>

<div>
<canvas id="canvas" width="400" height="300">
This text is displayed if your browser does not support HTML5 Canvas.
</canvas>
</div>

var canvas;
var ctx;
var x = 75;
var y = 50;
var WIDTH = 400;
var HEIGHT = 300;
var dragok = false;

function rect(x,y,w,h) {
ctx.beginPath();
ctx.rect(x,y,w,h);
ctx.closePath();
ctx.fill();
}

function clear() {
ctx.clearRect(0, 0, WIDTH, HEIGHT);
}

function init() {
canvas = document.getElementById("canvas");
ctx = canvas.getContext("2d");
return setInterval(draw, 10);
}

function draw() {
clear();
ctx.fillStyle = "#FAF7F8";
rect(0,0,WIDTH,HEIGHT);
ctx.fillStyle = "#444444";
rect(x - 15, y - 15, 30, 30);
}

function myMove(e){
if (dragok){
x = e.pageX - canvas.offsetLeft;
y = e.pageY - canvas.offsetTop;
}
}

function myDown(e){
if (e.pageX < x + 15 + canvas.offsetLeft && e.pageX > x - 15 +
canvas.offsetLeft && e.pageY < y + 15 + canvas.offsetTop &&
e.pageY > y -15 + canvas.offsetTop){
x = e.pageX - canvas.offsetLeft;
y = e.pageY - canvas.offsetTop;
dragok = true;
canvas.onmousemove = myMove;
}
}

function myUp(){
dragok = false;
canvas.onmousemove = null;
}

init();
canvas.onmousedown = myDown;
canvas.onmouseup = myUp;

</script>

</section>
</body>
</html>