✔ Liste auf Doppelungen und fehlende Daten prüfen

$tmp = 1;

echo "<table><tr><td>Rechnung</td><td>Status</td></tr>";
if (($handle = fopen("ggr.csv", "r")) !== FALSE) 
{
  while (($data = fgetcsv($handle, 99999, ",")) !== FALSE)  
 
 {
  
 $dummy=intval(substr($data[0],5));  // nur Werte vergleichen, nicht Chars
  
 switch ($dummy)
 {
 
 case ($tmp==$dummy):
  
  echo "<tr><td>$data[0]</td><td>iO</td></tr>";
  $tmp++;
  break;
 
  case ($tmp>$dummy): // doppelt
  
  echo "<tr><td>$data[0]</td><td>doppelt</td</tr>";
 
  break;  
  case ($tmp<$dummy): // fehlt
  $tmp2=str_pad($tmp, 5 ,'0', STR_PAD_LEFT);  //mit Nullen auffüllen
 echo "<tr><td>GGR14".$tmp2."</td><td>fehlt</td></tr>";
 $tmp++;
  
  
  break;
 default:
 break;
 
  }
 
  }
}
echo "</table>";
  fclose($handle);
?>

function csv_get_inconsistent_rows( $handle, $start = 1 ) {
  // collect affected rows (either occure never or more than once)
  $affected_rows = array();
  $last_index    = $start;

  while ( !feof( $handle ) ) {
    $data = fgetcsv( $handle, 99999, ',' );

    $current_index = (int) substr( $data[0], 5 );

    // same index as before
    if ( $current_index === $last_index ) {
      if ( !isset( $affected_rows[ $current_index ] ) ) {
        $affected_rows[ $current_index ] = 1;
      }

      // increment occurence of this index by 1
      ++$affected_rows[ $current_index ];
    // index is not the logical successor of the last index
    } elseif ( $current_index > $last_index + 1 ) {
      // create range of undefined indices
      $range         = range( $last_index + 1, $current_index - 1 );
      // append range to the affected rows and define their occurence as 0
      $affected_rows = array_merge( $affected_rows, array_fill_keys( $range, 0 ) );
    }
  }

  return $affected_rows;
}