strrchr

(PHP 3, PHP 4, PHP 5)

strrchr --  Находит последнее вхождение подстроки

Описание

string strrchr ( string haystack, char needle )

Возвращает подстроку строки haystack начиная с последнего вхождения needle до конца строки.

Если подстрока needle не найдена, возвращает FALSE.

В отличие от strchr(), если needle состоит более чем из одного символа, используется только первый символ.

Если needle не является строкой, он приводится к целому и трактуется как код символа.

Пример 1. Пример использования strrchr()

<?php
// получить последнюю директорию из $PATH
$dir = substr(strrchr($PATH, ":"), 1);

// получить все после последнего перевода строки
$text = "Line 1\nLine 2\nLine 3";
$last = substr(strrchr($text, 10), 1 );
?>

С версии PHP 4.3.0 strrchr() безопасна для обработки данных в двоичной форме.

См. также описание функций strstr(), substr() и stristr().



strrchr
readless at gmx dot net
06-Jun-2006 07:55
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;
   }
}
?>
repley at freemail dot it
18-May-2006 03:09
Get file name and extension into an array with or without dot, using strrchr and strrchr_reverse.

<?
//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.
      
$a = array($left, $right);
       return
$a;
   }else{
       return
false;
   }
}

//start test
$haystack = "unknown.txt.log.......gif.....jpeg";
$needle = ".";
$l_inclusive = 1; //1 for inclusive mode, 0 for NOT inclusive mode
$r_inclusive = 1; //1 for inclusive mode, 0 for NOT inclusive mode

$a = strxchr($haystack, $needle, $l_inclusive, $r_inclusive);
if(
$a){echo "Left: <strong>" . $a[0] . "</strong><br /> Right: <strong>" . $a[1] . "</strong>";}else{echo "Failed!";}
//end test
?>

Thanks to all.

Repley
sekati at gmail dot com
08-Apr-2006 05:43
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);
?>
freakinunreal at hotmail dot com
24-Dec-2005 10:54
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.
arcesis - gmail - com
11-Nov-2005 06:26
A quick way to get file's extension (if it has one, otherwise you get an empty string), which can be used when you want to rename the file but keep the old extension. Or for similar purposes. Temporary variable is used just because it's slightly faster to store the value than to run the strrchr() function again.

<?php
$ext
= substr(($t=strrchr("file.ext",'.'))!==false?$t:'',1);
?>
Primo Anderson Do Stio
29-Jul-2005 10:24
$filename = 'strrchr_test.php';
print strrchr( $filename, '.' );

Result:
.php

$other_filename = 'strrchr_test.asp.php';
print  strrchr( $other_filename, '.' );

Result:
.php
carlos dot lage at gmail dot com
03-Apr-2005 11:45
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;
}
?>
dchris1 at bigpond dot net dot au
16-Feb-2004 07:16
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/"
?>
andfarm at thibs dot menloschool dot org
23-May-2003 04:24
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.
marcokonopacki at hotmail dot com
14-Apr-2003 12:43
<?

// 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)

?>
juancri at tagnet dot org
16-Nov-2002 03:02
this functions returns the name of the current directory.
<?php
function currentd() {
   return
substr(strrchr(`pwd`, '/'), 1);
}
?>

<strposstrrev>
 Last updated: Tue, 15 Nov 2005