源码：
点击下载
<body>
<div align="center">
<canvas id="myCanvas" width="500" height="200" style="border:2px solid #6699cc"></canvas>
<div class="control-ops">
<button type="button" class="btn btn-primary" onclick="javascript:clearArea();return false;">清空画板</button>
Line width : <select id="selWidth">
<option value="1">1</option>
<option value="3">3</option>
<option value="5">5</option>
<option value="7">7</option>
<option value="9" selected="selected">9</option>
<option value="11">11</option>
</select>
Color : <select id="selColor">
<option value="black">black</option>
<option value="blue" selected="selected">blue</option>
<option value="red">red</option>
<option value="green">green</option>
<option value="yellow">yellow</option>
<option value="gray">gray</option>
</select>
</div>
</div>
<li><button onclick="javascript:UploadPic();return false;">上传到服务器</button></li>
<script>
var mousePressed = false;
var lastX, lastY;
var ctx;
function InitThis() {
ctx = document.getElementById('myCanvas').getContext("2d");
$('#myCanvas').mousedown(function (e) {
mousePressed = true;
Draw(e.pageX - $(this).offset().left, e.pageY - $(this).offset().top, false);
});
$('#myCanvas').mousemove(function (e) {
if (mousePressed) {
Draw(e.pageX - $(this).offset().left, e.pageY - $(this).offset().top, true);
}
});
$('#myCanvas').mouseup(function (e) {
mousePressed = false;
});
$('#myCanvas').mouseleave(function (e) {
mousePressed = false;
});
}
function Draw(x, y, isDown) {
if (isDown) {
ctx.beginPath();
ctx.strokeStyle = $('#selColor').val();
ctx.lineWidth = $('#selWidth').val();
ctx.lineJoin = "round";
ctx.moveTo(lastX, lastY);
ctx.lineTo(x, y);
ctx.closePath();
ctx.stroke();
}
lastX = x; lastY = y;
}
function clearArea() {
// Use the identity matrix while clearing the canvas
ctx.setTransform(1, 0, 0, 1, 0, 0);
ctx.clearRect(0, 0, ctx.canvas.width, ctx.canvas.height);
}
$(document).ready(function(){
InitThis();
})
function UploadPic() {
// Generate the image data
var Pic = document.getElementById("myCanvas").toDataURL("image/png");
Pic = Pic.replace(/^data:image\/(png|jpg);base64,/, "")
// Sending the image data to Server
$.ajax({
type: 'post',
url: 'upload.php'+'?'+ Math.random(),
data:{img:Pic},
dataType: 'json',
success: function (msg) {
alert("Done, Picture Uploaded.");
}
});
}
</script>
</body>
PHP部分
<?php
// requires php5
define('UPLOAD_DIR', 'images/');
var_dump($_POST);
$img = $_POST['img'];
$img = str_replace('data:image/png;base64,', '', $img);
$img = str_replace(' ', '+', $img);
$data = base64_decode($img);
$file = UPLOAD_DIR . uniqid() . '.png';
$success = file_put_contents($file, $data);
print $success ? $file : 'Unable to save the file.';
?>
