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] $file[1]<br>\n"; #file[0]=Unix timestamp; file[1]=filename
}
?>
rsort
(PHP 4, PHP 5, PHP 7)
rsort — 역순으로 배열 정렬
설명
bool rsort
( array
&$array
[, int $sort_flags
] )이 함수는 역순으로 배열을 정렬한다 (높은 것에서 낮은 것으로).
반환값
성공 시 TRUE를, 실패 시 FALSE를 반환합니다.
예제
Example #1 rsort() 예제
<?php
$fruits = array("lemon", "orange", "banana", "apple");
rsort($fruits);
foreach ($fruits as $key => $val) {
echo "$key = $val\n";
}
?>
위 예제의 출력:
0 = orange 1 = lemon 2 = banana 3 = apple
fruits는 알파벳 역순으로 정렬되었다.
주의
Note: 이 함수는
array에 새로운 키를 할당합니다. 이 작업은 단순히 키를 재배열할 뿐만 아니라, 이미 할당되어 있는 키를 제거할 수 있습니다.
add a note
User Contributed Notes 6 notes
Alex M ¶
18 years ago
ray at non-aol dot com ¶
19 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 ¶
22 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 ¶
20 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]
