title: Using LocalFileSystem to store and display images
body: <p>I tried to write a bit of code to retrieve an image file (from Wikimedia Commons), store it locally and then display it. Here my code:</p>
  
  <pre><code>&lt;!DOCTYPE html&gt; 
  &lt;html&gt; 
  &lt;head&gt;
  &lt;script&gt;
  
  window.requestFileSystem  = window.requestFileSystem || window.webkitRequestFileSystem;
  
  function onError(e) {
    console.log('Error', e);
  }
  
  var xhr = new XMLHttpRequest();
  xhr.open('GET', 'http://upload.wikimedia.org/wikipedia/fr/2/26/10_francs_Mathieu_1987_F365-28_revers.jpg', true);
  xhr.responseType = 'blob';
  
  xhr.onload = function(e) {
  
  window.requestFileSystem(PERSISTENT, 1024 * 1024, function(fs) {alert(fs.root.name);}, onError);
  
    window.requestFileSystem(PERSISTENT, 1024 * 1024, function(fs) {
      fs.root.getFile('image.jpg', {create: true}, function(fileEntry) {
        fileEntry.createWriter(function(writer) {
  
          writer.onwrite = function(e) {};
          writer.onerror = function(e) {};
  
          var blob = new Blob([xhr.response], {type: 'image/jpeg'});
  
          writer.write(blob);
  
        }, onError);
      }, onError);
    }, onError);
  
    window.requestFileSystem(PERSISTENT, 1024 * 1024, function(fs) {
      fs.root.getFile('image.jpg', {create: false}, function(fileEntry) {
          fileEntry.file(function(file) {
              var reader = new FileReader();
              reader.onloadend = function(event) {
                  var img = document.createElement("img");
                  img.src = event.target.result;
  
                  document.body.parentNode.insertBefore(img, document.body.nextSibling);
              };
              reader.readAsDataURL(file);
          }, onError);
      }, onError);
    }, onError);
  
  };
  
  xhr.send();
  &lt;/script&gt;
  &lt;/head&gt; 
  &lt;body&gt;
  
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>Nothing is displayed. Chrome's console doesn't display any error message, so I have no idea why it's not working. Any clue?</p>
  
  <p>Edit :</p>
  
  <p>I have just seen I actually get a FileError, code 10, which means QUOTA_EXCEEDED_ERR, even if I start my Google Chrome with these parameters:</p>
  
  <pre><code>"C:\Program Files\Google\Chrome\Application\chrome.exe" --allow-file-access-from-files --unlimited-quota-for-files
  </code></pre>
  
  <p>Actually, I get the same error with or without the <code>--unlimited-quota-for-files</code> parameter, which is weird. But I get a File Error 2 without <code>--allow-file-access-from-files</code></p>