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
}
?>
rsort
(PHP 4, PHP 5, PHP 7, PHP 8)
rsort — Ordena un array en orden inverso
Descripción
Esta función ordena un array en orden inverso (mayor a menor).
Nota:
Si dos miembros se comparan como iguales, su orden relativo en el array oredenado será indefinido.
Parámetros
-
array -
El array de entrada.
-
sort_flags -
Quizá se necesita cambiar el comportamiento de ordenado usando el parámetro opcional
sort_flags, para más información ver sort().
Valores devueltos
Devuelve true en caso de éxito o false en caso de error.
Ejemplos
Ejemplo #1 Ejemplo de rsort()
<?php
$fruits = array("limón", "naranja", "plátano", "manzana");
rsort($fruits);
foreach ($fruits as $key => $val) {
echo "$key = $val\n";
}
?>El resultado del ejemplo sería:
0 = plátano 1 = naranja 2 = manzana 3 = limón
Las frutas han sido ordenadas alfábeticamente pero en orden inverso.
Notas
Nota: Esta función asigna nuevas clave a los elemenos del
array. Eliminará cualquier clave existente que haya sido asignada, en lugar de reordenar las claves.
Ver también
- arsort() - Ordena un array en orden inverso y mantiene la asociación de índices
- krsort() - Ordena un array por clave en orden inverso
- comparación de funciones de orden de arrays
add a note
User Contributed Notes 6 notes
Alex M ¶
19 years ago
ray at non-aol dot com ¶
20 years ago
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.
pshirkey at boosthardware dot com ¶
19 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");
slevy1 at pipeline dot com ¶
23 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 ¶
21 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.
suniafkhami at gmail dot com ¶
10 years ago
If you are sorting an array from a database result set, such as MySQL for example, another approach could be to have your database sort the result set by using ORDER BY DESC, which would be the equivalent of using rsort() on the resulting array in PHP.
[Edited by moderator for clarity: googleguy at php dot net]
