array sorting

[Anon]

Hi!

I need a little bit help with sorting. Lets say I read a file which contains several lines like following:

id||time||subject||sender

If I read the file using file I get array where are values like line above.
$array1 = file("file.txt");

If I now explode all the lines and store in another array I get an array with several sub-arrays.
foreach ($array1 as $array2) {
$array2 = explode("||", $array2);
$array[$array["0"]] = $array;
}

Now, how can I sort those sub arrays by time,subject and sender. There is need to sort only by time/subject or sender, not all of them at the same time.

This might sound confusing but I hope you figure out what I am aiming at.

Thanks to all beforehand!

• Markus

[Anon]

You need array_multisort. Something like this, although you'd need to work out how to select the sort you want (presumably based on a form input).

$fcontents = file("file.txt");
while (list ($line_num, $line) = each ($fcontents)) {
// split line
$field = explode("||", $line);
// build up separate arrays
$id[] = $field[0];
$time[] = $field[1];
$subject[] = $field[2];
$sender[] = $field[3];
}
array_multisort ($time,$subject,$sender,$id);
or
array_multisort ($subject,$time,$sender,$id);
or
array_multisort ($sender,$time,$subject,$id);

The sort is on the first array's contents, with the others used to resolve equal sort keys. The contents of all the arrays are sorted along with the first one.

I was using this as a laborious way to reverse a file's contents until I realised that there is an array_reverse function ... !