title: Parse Wordpress JSON with PHP
body: <p>For me as a PHP beginner the JSON structure stored by Wordpress in the mySql database is quite complex. But I would like to get certain information out of a complex JSON structure. Could you please help to get the data out of this JSON string in a human friendly structure by using PHP?</p>
  
  <p>I want to get the filenames near the "file" elements:</p>
  
  <pre><code>a: 5: {
  s: 5: "width";i: 428;s: 6: "height";i: 324;s: 4: "file";s: 15: "Clipboard12.jpg";s: 5: "sizes";a: 9: {
      s: 9: "thumbnail";a: 4: {
          s: 4: "file";s: 23: "Clipboard12-150x150.jpg";s: 5: "width";i: 150;s: 6: "height";i: 150;s: 9: "mime-type";s: 10: "image/jpeg";
      }
      s: 6: "medium";a: 4: {
          s: 4: "file";s: 23: "Clipboard12-300x227.jpg";s: 5: "width";i: 300;s: 6: "height";i: 227;s: 9: "mime-type";s: 10: "image/jpeg";
      }
      s: 14: "post-thumbnail";a: 4: {
          s: 4: "file";s: 22: "Clipboard12-100x65.jpg";s: 5: "width";i: 100;s: 6: "height";i: 65;s: 9: "mime-type";s: 10: "image/jpeg";
      }
      s: 9: "art-thumb";a: 4: {
          s: 4: "file";s: 22: "Clipboard12-100x65.jpg";s: 5: "width";i: 100;s: 6: "height";i: 65;s: 9: "mime-type";s: 10: "image/jpeg";
      }
      s: 8: "art-wide";a: 4: {
          s: 4: "file";s: 23: "Clipboard12-326x159.jpg";s: 5: "width";i: 326;s: 6: "height";i: 159;s: 9: "mime-type";s: 10: "image/jpeg";
      }
      s: 12: "art-big-1col";a: 4: {
          s: 4: "file";s: 23: "Clipboard12-326x235.jpg";s: 5: "width";i: 326;s: 6: "height";i: 235;s: 9: "mime-type";s: 10: "image/jpeg";
      }
      s: 15: "art-slide-small";a: 4: {
          s: 4: "file";s: 23: "Clipboard12-326x324.jpg";s: 5: "width";i: 326;s: 6: "height";i: 324;s: 9: "mime-type";s: 10: "image/jpeg";
      }
      s: 7: "art-gal";a: 4: {
          s: 4: "file";s: 23: "Clipboard12-210x210.jpg";s: 5: "width";i: 210;s: 6: "height";i: 210;s: 9: "mime-type";s: 10: "image/jpeg";
      }
      s: 10: "td_198x143";a: 4: {
          s: 4: "file";s: 23: "Clipboard12-198x143.jpg";s: 5: "width";i: 198;s: 6: "height";i: 143;s: 9: "mime-type";s: 10: "image/jpeg";
      }
  }
  s: 10: "image_meta";a: 11: {
      s: 8: "aperture";i: 0;s: 6: "credit";s: 0: "";s: 6: "camera";s: 0: "";s: 7: "caption";s: 0: "";s: 17: "created_timestamp";i: 0;s: 9: "copyright";s: 0: "";s: 12: "focal_length";i: 0;s: 3: "iso";i: 0;s: 13: "shutter_speed";i: 0;s: 5: "title";s: 0: "";s: 11: "orientation";i: 0;
  }
  </code></pre>
  
  <p>}</p>
  
  <p>By executing the PHP file I would like to see as results:</p>
  
  <pre><code>Clipboard0340-100x65.jpg
  Clipboard0340-150x150.jpg
  Clipboard0340-198x143.jpg
  Clipboard0340-210x210.jpg
  Clipboard0340-300x209.jpg
  Clipboard0340-326x159.jpg
  Clipboard0340-326x235.jpg
  Clipboard0340-326x406.jpg
  Clipboard0340-513x357.jpg
  Clipboard0340-674x357.jpg
  Clipboard0340.jpg 
  </code></pre>