title: PHPExcel read empty cells
body: <p>I'm using PHPExcel library to get data from cells. I implemented <code>PHPExcel_Reader_IReadFilter</code> iterface and set it in my reader object to read data from custom <code>range(B1:J50 e.g)</code>. It works fine but reader doesn't get empty cells, but i need to get them. I call <code>IterateOnlyExistingCells(false)</code>, but reader ignoring my filter and get all cells.</p>
  
  <pre><code>class CellsFilter implements PHPExcel_Reader_IReadFilter {
          private $startCellName;
          private $startCellValue;
          private $endCellName;
          private $endCellValue;
          private $additionalCells;
  
  
          public function __construct($strRange)  {
              $this-&gt;initializeRange($strRange);          
          }
  
          public function readCell($column, $row, $worksheetName = '') {
  
              if ($row &gt;= $this-&gt;startCellValue &amp;&amp; $row &lt;= $this-&gt;endCellValue) {
                  if (in_array($column, range($this-&gt;startCellName, $this-&gt;endCellName))) {                   
                      return true;
                  }
              }
              return false;
          }
  </code></pre>