code: public function listWorksheetInfo($pFilename)
      {
          // Open file
          if (!$this->canRead($pFilename)) {
              throw new Exception($pFilename . ' is an Invalid Spreadsheet file.');
          }
          $this->openFile($pFilename);
          $fileHandle = $this->fileHandle;
  
          // Skip BOM, if any
          $this->skipBOM();
          $this->checkSeparator();
          $this->inferSeparator();
  
          $worksheetInfo = [];
          $worksheetInfo[0]['worksheetName'] = 'Worksheet';
          $worksheetInfo[0]['lastColumnLetter'] = 'A';
          $worksheetInfo[0]['lastColumnIndex'] = 0;
          $worksheetInfo[0]['totalRows'] = 0;
          $worksheetInfo[0]['totalColumns'] = 0;
  
          // Loop through each line of the file in turn
          while (($rowData = fgetcsv($fileHandle, 0, $this->delimiter, $this->enclosure)) !== false) {
              ++$worksheetInfo[0]['totalRows'];
              $worksheetInfo[0]['lastColumnIndex'] = max($worksheetInfo[0]['lastColumnIndex'], count($rowData) - 1);
          }
  
          $worksheetInfo[0]['lastColumnLetter'] = Coordinate::stringFromColumnIndex($worksheetInfo[0]['lastColumnIndex'] + 1);
          $worksheetInfo[0]['totalColumns'] = $worksheetInfo[0]['lastColumnIndex'] + 1;
  
          // Close file
          fclose($fileHandle);
  
          return $worksheetInfo;
      }
docs: Return worksheet info (Name, Last Column Letter, Last Column Index, Total Rows, Total Columns).
  
  @param string $pFilename
  
  @throws Exception
  
  @return array