flat file - sort by key not title

generic

Hi,

I've got this peice of code that basically does what I need except when I delete a row from the text file, it rewrites the rest of the file alphabetically by title instead of alphabetically by id. Can anyone help me sort this out (I know, I know - horrible pun...)

file.txt

3|Third Entry
2|Second Entry
1|First Entry

admin.php

<?

$file = 'file.txt';

if ( isset ( $_POST['delete'] ) )
{
     $trap = array ();

 foreach ( $_POST['delete'] AS $item )
 {
      if ( ( $new = intval ( $item ) ) != 0 && ! in_array ( $new, $trap ) )
      {
           $trap[] = $new;
      }
 }

 if ( ! empty ( $trap ) )
 {
      $keep = array ();

      $io = file ( $file );

      for ( $i = 0; $i < sizeof ( $io ); $i++ )
      {
           $parts = explode ( '|', $io[$i] );

           if ( ! in_array ( $parts[0], $trap ) )
           {
                $keep[] = trim ( $parts[1] );
           }
      }

      $data = '';

      for ( $i = ( sizeof ( $keep ) - 1 ); $i >= 0; $i-- )
      {
           $$data = $data . ( $i + 1 ) . "|" . $keep[$i] . "\r\n";
      }

      $io = fopen ( $file, 'w' );
      fputs ( $io, substr ( $data, 0, -2 ) );
      fclose ( $io );

 }
}

echo "<center>\r\n";
echo "Add New Title:<br /><br />\r\n";
echo "<form action='" . $_SERVER['PHP_SELF'] . "' method='post'>\r\n";
echo "New Title<br /><br />\r\n";
echo "<input type='text' name='new_title'><br /><br />\r\n";
echo "<input type='submit' value='Save Data >>'>\r\n";
echo "</form><br /><br /><br /><br />\r\n";

if ( isset ( $_POST['new_title'] ) )
{
     $title = trim ( $_POST['new_title'] );
     $io = fopen ( $file, 'r+' );
     $line = fgets ( $io, 4096 );
     $new_data = ( substr ( $line, 0, strpos ( $line, '|' ) ) + 1 ) . "|" . $title . "\r\n";
     fseek ( $io, 0 );
     while ( ! feof ( $io ) )
     {
          $new_data .= fgets ( $io, 4096 );
     }

 fseek ( $io, 0 );
 fputs ( $io, $new_data );
 fclose ( $io );
}

echo "Remove Titles:<br /><br />\r\n";
echo "<form action='" . $_SERVER['PHP_SELF'] . "' method='post'>\r\n";
echo "News Titles<br /><br />\r\n";
echo "<select name='delete[]' size='5' multiple>\r\n";
     $io = file ( $file );

 for ( $i = 0; $i < sizeof ( $io ); $i++ )
 {
      $x = explode ( '|', $io[$i] );
      echo "<option value='" . $x[0] . "'> " . trim ( $x[1] ) . "\r\n";
 }
echo "</select><br /><br />\r\n";
echo "<input type='submit' value='Delete Data >>'>\r\n";
echo "</form><br /><br /><br /><br />\r\n";
echo "</center>\r\n";

?>

Weedpacket

I'm pretty sure that "$$data" is making things go screwy for you.

$io = file($file);
$records = array();
foreach($io as $line)
{
    list($id,$data) = explode('|',$line);
    $records[$id] = trim($line);
}
unset($io);
foreach($trap as $trapped)
  unset($records[$trapped]);
ksort($records); // Probably not needed, but just in case the input file was missorted
$data = array();
foreach($records as $key=>$title)
    $data[] = $key.'|'.$title;
$data = join("\r\n", $data);
$io = fopen ( $file, 'w' );
fwrite ( $io, $data, strlen($data) );
fclose ( $io );

generic

Hmm.. I changed it to that and again, weirdness abounds. When I delete say, the third one, the file ends up going from:

to:

1|1|First Title
2|2|Second Title
4|4|Fourth Title
5|5|Fifth Title

Any further ideas?

Weedpacket

(a) I didn't know you wanted it in descending order (change the sort function).
(b) I made a typo and put $line in the array instead of $data (the line after the explode() should have looked strange).
(c) I often don't test the code I post here, leaving that and any consequent debugging to be done by the person using it as a guideline with their own understanding of what they want it to do.

generic

Thanks for your help, I got it working. Much stress has been relieved... Cheers!