reset
Like sort(), rsort() assigns new keys for the elements in array. It will remove any existing keys you may have assigned, rather than just reordering the keys. This means that it will destroy associative keys.
$animals = array("dog"=>"large", "cat"=>"medium", "mouse"=>"small");
print_r($animals);
//Array ( [dog] => large [cat] => medium [mouse] => small )
rsort($animals);
print_r($animals);
//Array ( [0] => small [1] => medium [2] => large )
Use KSORT() or KRSORT() to preserve associative keys.
rsort
(PHP 4, PHP 5)
rsort — Sortuj tablicę w porządku odwrotnym
Opis
void rsort
( array
&$tablica
[, int $flagi
] )Ta funkcja sortuje tablicę w porządku odwrotnym (od największego do najmniejszego).
Informacja: Ta funkcja przypisuje nowe klucze dla elementów argumentu
tablica. Wszystkie istniejące klucze zostaną usunięte.
Zwraca TRUE w przypadku powodzenia, FALSE w
przypadku błędu.
Przykład #1 Przykład użycia rsort()
<?php
$owoce = array("cytryna", "pomarańcza", "banan", "jabłko");
rsort($owoce);
foreach ($owoce as $key => $val) {
echo "$key = $val\n";
}
?>
Powyższy przykład wyświetli:
0 = pomarańcza 1 = jabłko 2 = cytryna 3 = banan
Owoce zostały posortowane w odwrotnym porządku alfabetycznym.
Możesz zmodyfikować zachowanie sortowania przez użycie opcjonalnego
parametru flagi. Aby uzyskać szczegóły zobacz
sort().
Patrz także: arsort(), asort(), ksort(), krsort(), sort() i usort().
add a note
User Contributed Notes
rsort - [5 notes]
ray at non-aol dot com ¶
8 years ago
slevy1 at pipeline dot com ¶
12 years ago
I thought rsort was working successfully or on a multi-dimensional array of strings that had first been sorted with usort(). But, I noticed today that the array was only partially in descending order. I tried array_reverse on it and that seems to have solved things.
rnk-php at kleckner dot net ¶
10 years ago
Apparently rsort does not put arrays with one value back to zero. If you have an array like: $tmp = array(9 => 'asdf') and then rsort it, $tmp[0] is empty and $tmp[9] stays as is.
pshirkey at boosthardware dot com ¶
8 years ago
I needed a function that would sort a list of files into reversed order based on their modification date.
Here's what I came up with:
function display_content($dir,$ext){
$f = array();
if (is_dir($dir)) {
if ($dh = opendir($dir)) {
while (($folder = readdir($dh)) !== false) {
if (preg_match("/\s*$ext$/", $folder)) {
$fullpath = "$dir/$folder";
$mtime = filemtime ($fullpath);
$ff = array($mtime => $fullpath);
$f = array_merge($f, $ff);
}
}
rsort($f, SORT_NUMERIC);
while (list($key, $val) = each($f)) {
$fcontents = file($val, "r");
while (list($key, $val) = each($fcontents))
echo "$val\n";
}
}
}
closedir($dh);
}
Call it like so:
display_content("folder","extension");
Alex M ¶
7 years ago
A cleaner (I think) way to sort a list of files into reversed order based on their modification date.
<?php
$path = $_SERVER[DOCUMENT_ROOT]."/files/";
$dh = @opendir($path);
while (false !== ($file=readdir($dh)))
{
if (substr($file,0,1)!=".")
$files[]=array(filemtime($path.$file),$file); #2-D array
}
closedir($dh);
if ($files)
{
rsort($files); #sorts by filemtime
#done! Show the files sorted by modification date
foreach ($files as $file)
echo "$file[0] $file[1]<br>\n"; #file[0]=Unix timestamp; file[1]=filename
}
?>