<?php
/**
* Removes the preceeding or proceeding portion of a string
* relative to the last occurrence of the specified character.
* The character selected may be retained or discarded.
*
* Example usage:
* <code>
* $example = 'http://example.com/path/file.php';
* $cwd_relative[] = cut_string_using_last('/', $example, 'left', true);
* $cwd_relative[] = cut_string_using_last('/', $example, 'left', false);
* $cwd_relative[] = cut_string_using_last('/', $example, 'right', true);
* $cwd_relative[] = cut_string_using_last('/', $example, 'right', false);
* foreach($cwd_relative as $string) {
* echo "$string <br>".PHP_EOL;
* }
* </code>
*
* Outputs:
* <code>
* http://example.com/path/
* http://example.com/path
* /file.php
* file.php
* </code>
*
* @param string $character the character to search for.
* @param string $string the string to search through.
* @param string $side determines whether text to the left or the right of the character is returned.
* Options are: left, or right.
* @param bool $keep_character determines whether or not to keep the character.
* Options are: true, or false.
* @return string
*/
function cut_string_using_last($character, $string, $side, $keep_character=true) {
$offset = ($keep_character ? 1 : 0);
$whole_length = strlen($string);
$right_length = (strlen(strrchr($string, $character)) - 1);
$left_length = ($whole_length - $right_length - 1);
switch($side) {
case 'left':
$piece = substr($string, 0, ($left_length + $offset));
break;
case 'right':
$start = (0 - ($right_length + $offset));
$piece = substr($string, $start);
break;
default:
$piece = false;
break;
}
return($piece);
}
?>
strrchr
(PHP 4, PHP 5, PHP 7)
strrchr — 문자열에서 문자가 마지막으로 나오는 부분을 찾습니다
설명
이 함수는 needle가 마지막으로 나오는 위치부터
haystack의 마지막까지의
haystack 문자열 부분을 반환합니다.
인수
-
haystack -
탐색할 문자열
-
needle -
needle이 하나 이상의 문자를 가지고 있으면, 첫번째 문자만 사용합니다. 이 동작은 strstr()과 다릅니다.needle이 문자열이 아니면, 정수로 변환하여 해당하는 값의 문자를 취합니다.
반환값
문자열의 부분을 반환하거나, needle이 발견되지 않으면
FALSE를 반환합니다.
변경점
| 버전 | 설명 |
|---|---|
| 4.3.0 | 이 함수는 바이너리 안전입니다. |
예제
Example #1 strrchr() 예제
<?php
// $PATH에서 마지막 디렉토리를 얻는다.
$dir = substr(strrchr($PATH, ":"), 1);
// 마지막 줄바꿈 다음의 문자열을 얻는다.
$text = "줄 1\n줄 2\n줄 3";
$last = substr(strrchr($text, 10), 1);
?>
주의
Note: 이 함수는 바이너리 안전입니다.
add a note
User Contributed Notes 10 notes
matthewkastor at live dot com ¶
13 years ago
sekati at gmail dot com ¶
18 years ago
just a small addition to carlos dot lage at gmail dot com note which makes it a bit more useful and flexible:
<?php
// return everything up to last instance of needle
// use $trail to include needle chars including and past last needle
function reverse_strrchr($haystack, $needle, $trail) {
return strrpos($haystack, $needle) ? substr($haystack, 0, strrpos($haystack, $needle) + $trail) : false;
}
// usage:
$ns = (reverse_strrchr($_SERVER["SCRIPT_URI"], "/", 0));
$ns2 = (reverse_strrchr($_SERVER["SCRIPT_URI"], "/", 1));
echo($ns . "<br>" . $ns2);
?>
dchris1 at bigpond dot net dot au ¶
20 years ago
The function provided by marcokonopacki at hotmail dot com isn't really a reverse-version of strrchr(), rather a reverse version of strchr(). It returns everything from the start of $haystack up to the FIRST instance of the $needle. This is basically a reverse of the behavior which you expect from strchr(). A reverse version of strrchr() would return everything in $haystack up to the LAST instance of $needle, eg:
<?php
// reverse strrchr() - PHP v4.0b3 and above
function reverse_strrchr($haystack, $needle)
{
$pos = strrpos($haystack, $needle);
if($pos === false) {
return $haystack;
}
return substr($haystack, 0, $pos + 1);
}
?>
Note that this function will need to be modified slightly to work with pre 4.0b3 versions of PHP due to the return type of strrpos() ('0' is not necessarily 'false'). Check the documentation on strrpos() for more info.
A function like this can be useful for extracting the path to a script, for example:
<?
$string = "/path/to/the/file/filename.php";
echo reverse_strrchr($string, '/'); // will echo "/path/to/the/file/"
?>
Primo Anderson Do S?tio ¶
19 years ago
$filename = 'strrchr_test.php';
print strrchr( $filename, '.' );
Result:
.php
$other_filename = 'strrchr_test.asp.php';
print strrchr( $other_filename, '.' );
Result:
.php
readless at gmx dot net ¶
18 years ago
to: repley at freemail dot it
the code works very well, but as i was trying to cut script names (e.g.: $_SERVER["SCRIPT_NAME"] => /index.php, cut the string at "/" and return "index.php") it returned nothing (false). i've modified your code and now it works also if the needle is the first char.
- regards from germany
<?php
//strxchr(string haystack, string needle [, bool int leftinclusive [, bool int rightinclusive ]])
function strxchr($haystack, $needle, $l_inclusive = 0, $r_inclusive = 0){
if(strrpos($haystack, $needle)){
//Everything before last $needle in $haystack.
$left = substr($haystack, 0, strrpos($haystack, $needle) + $l_inclusive);
//Switch value of $r_inclusive from 0 to 1 and viceversa.
$r_inclusive = ($r_inclusive == 0) ? 1 : 0;
//Everything after last $needle in $haystack.
$right = substr(strrchr($haystack, $needle), $r_inclusive);
//Return $left and $right into an array.
return array($left, $right);
} else {
if(strrchr($haystack, $needle)) return array('', substr(strrchr($haystack, $needle), $r_inclusive));
else return false;
}
}
?>
freakinunreal at hotmail dot com ¶
18 years ago
to marcokonopacki at hotmail dot com.
I had to make a slight change in your function for it to return the complete needle inclusive.
// Reverse search of strrchr.
function strrrchr($haystack,$needle)
{
// Returns everything before $needle (inclusive).
//return substr($haystack,0,strpos($haystack,$needle)+1);
// becomes
return substr($haystack,0,strpos($haystack,$needle)+strlen($needle));
}
Note: the +1 becomes +strlen($needle)
Otherwise it only returns the first character in needle backwards.
marcokonopacki at hotmail dot com ¶
21 years ago
<?
// Reverse search of strrchr.
function strrrchr($haystack,$needle)
{
// Returns everything before $needle (inclusive).
return substr($haystack,0,strpos($haystack,$needle)+1);
}
$string = "FIELD NUMBER(9) NOT NULL";
echo strrrchr($string,")"); // Will print FIELD (9)
?>
carlos dot lage at gmail dot com ¶
19 years ago
I used dchris1 at bigpond dot net dot au 's reverse strrchr and reduced it to one line of code and fixed it's functionality - the real strrchr() returns FALSE if the needle is not found, not the haystack :)
<?php
// reverse strrchr()
function reverse_strrchr($haystack, $needle)
{
return strrpos($haystack, $needle) ? substr($haystack, 0, strrpos($haystack, $needle) +1 ) : false;
}
?>
andfarm at thibs dot menloschool dot org ¶
21 years ago
strrchr is also very useful for finding the extension of a file. For example:
$ext = strrchr($filename, ".");
and $ext will contain the extension of the file, including a ".", if the file has an extension, and FALSE if the file has no extension. If the file has multiple extensions, such as "evilfile.jpg.vbs", then this construction will just return the last extension.
alex_bb23 at yahoo.co.uk ¶
7 years ago
I think that a good way (I don't know if is the best one) to extract a portion from a string:
<?php
$image = "image.name.jpg";
// get file extension
preg_replace("/.*\.(.*)$/", "$1", $last);
// will result: jpg
?>
Is faster that substr(strrchr...
