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strrchr

(PHP 3, PHP 4, PHP 5)

strrchr --  Find the last occurrence of a character in a string

Description

string strrchr ( string haystack, string needle )

This function returns the portion of haystack which starts at the last occurrence of needle and goes until the end of haystack.

Returns FALSE if needle is not found.

If needle contains more than one character, only the first is used in PHP 4. This behavior is different from that of strchr().

If needle is not a string, it is converted to an integer and applied as the ordinal value of a character.

例子 1. strrchr() example

<?php
// get last directory in $PATH
$dir = substr(strrchr($PATH, ":"), 1);

// get everything after last newline
$text = "Line 1\nLine 2\nLine 3";
$last = substr(strrchr($text, 10), 1 );
?>

strrchr() has been binary safe since PHP 4.3.0

See also strstr(), substr(), and stristr().


add a note add a note User Contributed Notes
readless at gmx dot net
07-Jun-2006 10:55
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
19-May-2006 06:09
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
09-Apr-2006 08:43
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
25-Dec-2005 02:54
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 10:26
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
30-Jul-2005 01:24
$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
04-Apr-2005 02:45
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
17-Feb-2004 11:16
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
24-May-2003 07:24
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
15-Apr-2003 03:43
<?

// 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
17-Nov-2002 07:02
this functions returns the name of the current directory.
<?php
function currentd() {
   return substr(strrchr(`pwd`, '/'), 1);
}
?>
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