sorting a text file

[chrislive]

basically what I want to do is to open a text file, extract that information, sort it, remove any blank lines, and then re-write the sorted information.

However i have looked around and I end up confused about how to use arrays properly and my results end up being useless 😛

the text file has different items on new lines so it looks like

item 1
item 3
item 2

how would i do this. i guess i need to open and create an array (this confuses me) and then sort it and compile the array back into normal text and add back into the file..

Thanks for your help

Thanks
Chris

[LordShryku]

You can look up these functions. The premise is pretty simple...

$file  = '/path/to/file.txt';

if(($array = file($file)) !== false) {
   # we have an array
   foreach($array as $key => $line) {
      # loop through and remove blank lines
      if(empty(trim($line)) {
         unset($array[$key]);
      }
   }

   # natural order sort
   natsort($array);

   # open and write
   if(($handle = fopen($file, 'w+')) !== false) {
      fwrite($handle, implode('', $array));
      fclose($handle);
   }
   else {
      echo "Couldn't open ".$file." for writing";
   }
}
else {
   echo "Couldn't read ".$file;
}

[chrislive]

thanks for your reply.. the sorting works however this part didnt

      if(empty(trim($line)) { 
         unset($array[$key]); 
     } 

also if the text file does not have a trailing row (extra line with no content at the end) the results will end up as

in the case of

item1
item3
item2

item1item2
item3

any ideas how to stop that...

THANKS ALOT!!!

[LordShryku]

The one line was just missing a closing paren. I haven't tested any of this. If you wanted to, you culd manually strip and replace the CRLF's.

$file = '/path/to/file.txt';
$new  = array(); # We'll store the good content here 

if(($array = file($file)) !== false) {
   # we have an array
   foreach($array as $key => $line) {
      # loop through and remove blank lines
      $line = str_replace("\n", "", $line);
      $line = str_replace("\r", "", $line);
      if(!empty($line)) {
         $new[] = $line; # not empty, add to new array
      }
   }

   # natural order sort
   natsort($new); # sort new array

   # open and write
   if(($handle = fopen($file, 'w+')) !== false) {
      fwrite($handle, implode("\n", $new)); # Implode with newlines
      fclose($handle);
   }
   else {
      echo "Couldn't open ".$file." for writing";
   }
}
else {
   echo "Couldn't read ".$file;
}