I just wrote a little function for sort an array in reverse order WITHOUT pre-ordering the numbers in it..
I hope, someone can use it. ;)
<?php
function rsort_rec($array)
{
if ( !is_array($array) ) return $array; # return original input when it's not an array
$c = count($array);
$c--;
$j = -1;
for ( $i = $c; $i > -1; $i-- )
{
$array_rec[] = $array[$i];
}
return $array_rec;
}
$input = array(167, 20, 100, 205);
print_r(rsort($input)); # printout reordered array with rsort()
# Output: Array ( [0] => 205 [1] => 167 [2] => 100 [3] => 20 )
print_r(rsort_rec($input)); # printout reordered array with rsort_rec()
# Output: Array ( [0] => 205 [1] => 100 [2] => 20 [3] => 167 )
?>
rsort
(PHP 4, PHP 5)
rsort — 配列を逆順にソートする
説明
bool rsort
( array &$array
[, int $sort_flags
] )
この関数は、配列を逆順に(高位から低位に)ソートします。
返り値
成功した場合に TRUE を、失敗した場合に FALSE を返します。
例
例1 rsort() の例
<?php
$fruits = array("lemon", "orange", "banana", "apple");
rsort($fruits);
foreach ($fruits as $key => $val) {
echo "$key = $val\n";
}
?>
上の例の出力は以下となります。
0 = orange 1 = lemon 2 = banana 3 = apple
fruits はアルファベットの逆順にソートされました。
注意
注意: この関数は、 array パラメータの要素に対して新しいキーを割り当てます。 その際、単純にキーを並べ替える代わりに、 すでに割り当てられている既存のキーを削除してしまいます。
rsort
manallesweg at gmx dot de
15-Jan-2008 07:03
15-Jan-2008 07:03
Alex M
28-Jun-2005 11:39
28-Jun-2005 11:39
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] $file[1]<br>\n"; #file[0]=Unix timestamp; file[1]=filename
}
?>
pshirkey at boosthardware dot com
14-Jan-2005 06:06
14-Jan-2005 06:06
I needed a function that would sort a list of files into reversed order based on their modification date.
Here's what I came up with:
function display_content($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");
ray at non-aol dot com
03-Nov-2004 12:49
03-Nov-2004 12:49
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.
rnk-php at kleckner dot net
17-Jun-2003 04:37
17-Jun-2003 04:37
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.
slevy1 at pipeline dot com
13-Jun-2001 03:15
13-Jun-2001 03:15
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.