Question

if I have an array like this (wihin a loop – so it is filled with more than 1 item of course):

$returnArray[] = array("type" => $dirinfo[0],"fileSize" => $this->ByteSize($dirinfo[1]),"fileName" => $dirinfo[2]);

The field “type” can be “folder” or “file”, but they are mixed together,
so like folder,file,file,folder,folder,file,etc

I would like to sort with the folders on top first and then the files… (like windows folder display behavior)

I’ve played with array_multisort, but just can’t get it to work…what should I do?

their example is this 9though I would like the same array returned just sorted, not a new array.:

foreach ($data as $key => $row) {
    $volume[$key]  = $row['volume'];
    $edition[$key] = $row['edition'];
}

// Sort the data with volume descending, edition ascending
// Add $data as the last parameter, to sort by the common key
array_multisort($volume, SORT_DESC, $edition, SORT_ASC, $data);

so I made this:

// tmp try sorting
        foreach ($returnArray as $key => $row) {
            $type[$key]         = $row['type'];
            $fileSize[$key]     = $row['fileSize'];
            $fileName[$key]     = $row['fileName']
        }

        // Sort the data with volume descending, edition ascending
        // Add $data as the last parameter, to sort by the common key
        array_multisort($type, SORT_DESC, $fileName, SORT_ASC, $fileSize, SORT_ASC, $rfileArray);

Answer 1

The first stop for such work is usort:

This function will sort an array by its values using a user-supplied
comparison function. If the array you wish to sort needs to be sorted
by some non-trivial criteria, you should use this function.

Basic usage is pretty simple:

function cmp($a, $b) {
    if ($a['type'] == $b['type']) {
        return 0; // equal
    }
    // If types are unequal, one is file and the other is folder.
    // Since folders should go first, they are "smaller".
    return $a['type'] == 'folder' ? -1 : 1;
}

usort($returnArray, "cmp");

From PHP 5.3 onwards, you can write the comparison function inline:

usort($returnArray, function($a, $b) {
    if ($a['type'] == $b['type']) {
        return 0;
    }
    return $a['type'] == 'folder' ? -1 : 1;
});

See also the very nice comparison of array sorting functions.