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POhow to save html5 canvas to server
 

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    <p>Im loading a few images to my canvas and then after they load I want to click a button that saves that canvas image to my server. I can see the script works fine until it gets to the 'toDataURL' part and my function stops executing. What am I doing wrong? Here is my code:</p> <pre><code>&lt;!DOCTYPE HTML&gt; &lt;html&gt; &lt;head&gt; &lt;style&gt; body { margin: 0px; padding: 0px; } &lt;/style&gt; &lt;/head&gt; &lt;body&gt; &lt;canvas id="myCanvas" width="578" height="200"&gt;&lt;/canvas&gt; &lt;div&gt; &lt;button onClick="saveCards();"&gt;Save&lt;/button&gt; &lt;/div&gt; &lt;script&gt; function loadImages(sources, callback) { var images = {}; var loadedImages = 0; var numImages = 0; // get num of sources for(var src in sources) { numImages++; } for(var src in sources) { images[src] = new Image(); images[src].onload = function() { if(++loadedImages &gt;= numImages) { callback(images); } }; images[src].src = sources[src]; } } var canvas = document.getElementById('myCanvas'); var context = canvas.getContext('2d'); var sources = { great: 'images/great.jpg', star: 'images/1Star.jpg', good: 'images/good.jpg' }; loadImages(sources, function(images) { context.drawImage(images.great, 0, 0, 80, 120); context.drawImage(images.star, 80, 0, 80, 120); context.drawImage(images.good, 160, 0, 80, 120); }); &lt;/script&gt; &lt;script type="text/javascript"&gt; function saveCards() { var canvas= document.getElementById("myCanvas"); alert("stops"); var theString= canvas.toDataURL(); var postData= "CanvasData="+theString; var ajax= new XMLHttpRequest(); ajax.open("POST", 'saveCards.php', true); ajax.setRequestHeader('Content-Type', 'canvas/upload'); ajax.onreadystatechange=function() { if(ajax.readyState == 4) { alert("image was saved"); }else{ alert("image was not saved"); } } ajax.send(postData); } &lt;/script&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <p>Thank you for any help is it because the images are not loaded before toDataUrl is called? If so can you please help me fix it. </p> <p>This is the php script:</p> <pre><code> &lt;?php if(isset($GLOBALS['HTTP_RAW_POST_DATA'])); { $rawImage=$GLOBALS['HTTP_RAW_POST_DATA']; $removeHeaders= substr($rawImage,strpos($rawImage, ",")+1); $decode=base64_decode($removeHeaders); $fopen= fopen('images/image.png', 'wb'); fwrite($fopen, $decode); fclose($fopen); } ?&gt; </code></pre> <p>I am getting a security error though.</p>
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    1. USjames
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    1. COAre you running this on a localhost or other server? Just asking.
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      1. USAtutouato
 

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