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POHTML5 Canvas - Saving and Restoring drag and drop canvas states
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copied!<p>I have a problem I am hoping someone is able to help with...</p> <p>Using this <strong><a href="http://jsfiddle.net/perl_user/TBh4k/8/" rel="nofollow">JSFIDDLE</a></strong> I am able to dynamically create canvases and drag and drop images between all the different canvases.</p> <pre><code>var next = 4 function addCanvas() { // create a new canvas element var newCanvas = document.createElement("canvas"); newCanvas.id = "addedcanvases" + next; //added this to give each new canvas a unique id next++; newCanvas.width = canvasWidth; newCanvas.height = canvasHeight; // add a context for the new canvas to the contexts[] array contexts.push(newCanvas.getContext("2d")); // link the new canvas to its context in the contexts[] array newCanvas.contextIndex = contexts.length; // wire up the click handler newCanvas.onclick = function (e) { handleClick(e, this.contextIndex); }; // wire up the mousemove handler newCanvas.onmousemove = function (e) { handleMousemove(e, this.contextIndex); }; // add the new canvas to the page document.body.appendChild(newCanvas); } </code></pre> <p><strong>The problem:</strong></p> <pre><code>$("#saveCanvasStates").click(function () { // save canvases and images on them to a database }); </code></pre> <p>At the end of doing some dragging and dropping between the canvases the user needs to be able to press a 'Save' button (shown here <strong><a href="http://jsfiddle.net/perl_user/TBh4k/8/" rel="nofollow">JSFIDDLE</a></strong>) that will save the current state of all the canvases to a <strong>database</strong> i.e:</p> <ul> <li>save all the canvases to the database</li> <li>save which images are on which canvases</li> </ul> <p><strong>This is so that the user can then come back at a later time and carry on from where they left off</strong> - with the dragging and dropping feature still working.</p> <p>What would be the best way of going about doing this? because there appears to be very little information/material on this particular topic, so your help with this will be much appreciated as would any JSFIDDLE examples that would be helpful - thanks a lot</p>

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