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strrchr> <strpbrk
Last updated: Fri, 28 Nov 2008

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strpos

(PHP 4, PHP 5)

strposFind position of first occurrence of a string

Description

int strpos ( string $haystack , mixed $needle [, int $offset ] )

Returns the numeric position of the first occurrence of needle in the haystack string. Unlike the strrpos() before PHP 5, this function can take a full string as the needle parameter and the entire string will be used.

Parameters

haystack

The string to search in

needle

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

offset

The optional offset parameter allows you to specify which character in haystack to start searching. The position returned is still relative to the beginning of haystack .

Return Values

Returns the position as an integer. If needle is not found, strpos() will return boolean FALSE.

Warning

This function may return Boolean FALSE, but may also return a non-Boolean value which evaluates to FALSE, such as 0 or "". Please read the section on Booleans for more information. Use the === operator for testing the return value of this function.

Examples

Example #1 Using ===

<?php
$mystring 
'abc';
$findme   'a';
$pos strpos($mystring$findme);

// Note our use of ===.  Simply == would not work as expected
// because the position of 'a' was the 0th (first) character.
if ($pos === false) {
    echo 
"The string '$findme' was not found in the string '$mystring'";
} else {
    echo 
"The string '$findme' was found in the string '$mystring'";
    echo 
" and exists at position $pos";
}
?>

Example #2 Using !==

<?php
$mystring 
'abc';
$findme   'a';
$pos strpos($mystring$findme);

// The !== operator can also be used.  Using != would not work as expected
// because the position of 'a' is 0. The statement (0 != false) evaluates 
// to false.
if ($pos !== false) {
     echo 
"The string '$findme' was found in the string '$mystring'";
         echo 
" and exists at position $pos";
} else {
     echo 
"The string '$findme' was not found in the string '$mystring'";
}
?>

Example #3 Using an offset

<?php
// We can search for the character, ignoring anything before the offset
$newstring 'abcdef abcdef';
$pos strpos($newstring'a'1); // $pos = 7, not 0
?>

Notes

Note: This function is binary-safe.



strrchr> <strpbrk
Last updated: Fri, 28 Nov 2008
 
add a note add a note User Contributed Notes
strpos
Tim
17-Nov-2008 05:52
If you would like to find all occurences of a needle inside a haystack you could use this function strposall($haystack,$needle);. It will return an array with all the strpos's.

<?php
/**
 * strposall
 *
 * Find all occurrences of a needle in a haystack
 *
 * @param string $haystack
 * @param string $needle
 * @return array or false
 */
function strposall($haystack,$needle){
   
   
$s=0;
   
$i=0;
   
    while (
is_integer($i)){
       
       
$i = strpos($haystack,$needle,$s);
       
        if (
is_integer($i)) {
           
$aStrPos[] = $i;
           
$s = $i+strlen($needle);
        }
    }
    if (isset(
$aStrPos)) {
        return
$aStrPos;
    }
    else {
        return
false;
    }
}
?>
Anonymous
28-Oct-2008 01:20
@samundra dot shr at gmail dot com

You can simplify this a lot by using str_replace to do the work for you
<?php
$filename
=$_POST['filename'];
if(!
$fpin=@fopen($filename,"r"))
{
    print
"<b>Error ! File Doesn't Exists</b>";
    exit();
}
$text='';
while(!
feof($fpin))
{
   
$text.=fread($fpin,1024);
}
$newtext = str_replace(array("\n", "\r"), '', $text);
$fp=fopen("sample.txt","wb+");
fwrite($fp,$newtext);
fclose($fp); 
print
"File Changed Successfully.";
?>

Or simply using php5 and not needing to do all the fread/fwrite
<?php
$filename
=$_POST['filename'];
if(
file_exists($filename)) {
   
file_put_contents('sample.txt', str_replace(array("\n", "\r"), '', file_get_contents($filename)));
}
else {
    print
"<b>Error ! File Doesn't Exists</b>";
}
?>
atomkirk at hotmail dot com
22-Oct-2008 06:19
careful that when you put a strpos in an if statement that you take note that if the string is in the 0 position it will return false, causing your control structure to think its not in the string.
samundra dot shr at gmail dot com
27-Sep-2008 11:40
This is the code,I wrote today, I wanted to strip all the newlines, and format the output in a single line so as to lower the filesize of my php source files.

<?php
/****************************************
@ Code By : Samundra Shrestha
@ Dated : September 28,2008
P.S. Remember to remove all single line comments from the source file
        otherwise the file may get corrupted.
******************************************/
if(!isset($_POST['change']) || !isset($_POST['filename']))
{
    print
"<b>".strtoupper("Paste the fullpath of the file")."</b>";
    print
"<form name='FrmChange' method='post' action='".$_SERVER['PHP_SELF']."'>";
    print
"<input type='textbox' name='filename' size='50px' maxlength='255'>";
    print
"<input type='submit' name='change' value='Start'>";
    print
"</form>";
}
else
{
$filename=$_POST['filename'];
if(!
$fpin=@fopen($filename,"r"))
{
    print
"<b>Error ! File Doesn't Exists</b>";
    exit();
}
$text="";
$i=0;
/*Put the contents of file into the string*/
while(!feof($fpin))
{
   
$text.=fread($fpin,1024);
}
$count=strlen($text);
$pos=strpos($text,"\n"); //Gives the First occurence of newline
while($i<$count)
{   
    if(
$i<$pos-1)
    {
       
$newtext.=$text{$i}; //C Style of String Indexing       
   
}
    else
    {
       
$pos=strpos($text,"\n",$i+1);
    }   
   
$i++;   
}
$newtext.="?>";   //necessary as somehow it is removed from the original source file.
$fp=fopen("sample.txt","wb+");
fwrite($fp,$newtext);
fclose($fp);   
print
"File Changed Successfully.";
}
?>

The resultant code is all in one new line saved in file sample.txt

I hope, this comes handy to someone.

Cheers,
Samundra Shrestha
http://www.samundra.com.np
mickRacky
19-Sep-2008 11:17
here's a php implementation of stdc++ string class find_first_of using strpos.

<?php
function find_first_of($haystack, $needlesAsString, $offset=0)
{
 
$max = strlen($needlesAsString);
 
$index = strlen($haystack)+1;
  for(
$ii=0; $ii<$max;$ii++){
   
$result = strpos($haystack,$needlesAsString[$ii], $offset);
    if(
$result !== FALSE  && $result < $index)
     
$index = $result;
  }
  return (
$index > strlen($haystack)? FALSE: $index);
}
?>

Example:
<?php
$test
="Ralph: One of these days, Alice!!";
$look_for=":!,";   // punctuation marks

$ss = 0;
while(
$answer=find_first_of($test,$look_for,$ss) ) {
  echo
$answer . "\n";
 
$ss = $answer+1;
 }
?>

This prints out:
5
24
31
32
Wartosh
22-Aug-2008 02:01
Hi,

Chuzasoft Inc : maybe I haven't understood your goal clearly, but I think there is a faster way to determinate whether a pattern is contained in a string (like using the " LIKE '%bla bla%' " in SQL).
You should read about "Regular Expression" (powerfull string operations are allowed using it) : http://fr.php.net/manual/en/book.pcre.php

Your example, it should be written like this :

<?
$myString
= "Hi, this is good!";
$srchStrg = ".*thi.* goo.*";
$srchRes  = preg_match("/$searchThis/", $myString);

if (
$searchResult != 0 )
    echo
"TRUE: string has been found :-)";
else
    echo
"FALSE: string wasn't found :'-(";
?>

Sincerely
Chuzasoft Inc. ARGENTINA
05-Aug-2008 12:16
Hi! Don't you people miss the pretty comparison operator 'LIKE' from mySql in PHP??.
I've made this funtion to emulate that method. It's for search a match string into another String
using the '%' caracter just like you do un the LIKE syntax.
For example:

<?php
$mystring
= "Hi, this is good!";
$searchthis = "%thi% goo%";

$resp = milike($mystring,$searchthis);

       
if (
$resp){
   echo
"milike = VERDADERO";
} else{
   echo
"milike = FALSO";
}

?>
Will print:
milike = VERDADERO

and so on...

this is the function:

<?php
function milike($cadena,$busca){
    if(
$busca=="") return 1;
   
   
$vi = split("%",$busca);
    
$offset=0;
    for(
$n=0;$n<count($vi);$n++){
        if(
$vi[$n]== ""){
            if(
$vi[0]== ""){
                  
$tieneini = 1;
            }
        } else {
           
$newoff=strpos($cadena,$vi[$n],$offset);
            if(
$newoff!==false){
                if(!
$tieneini){
                    if(
$offset!=$newoff){
                        return
false;
                    }
                }
                if(
$n==count($vi)-1){
                    if(
$vi[$n] != substr($cadena,strlen($cadena)-strlen($vi[$n]), strlen($vi[$n]))){
                        return
false;
                    }

                } else {
                   
$offset = $newoff + strlen($vi[$n]);
                 }
            } else {
                return
false;
            }
        }
    }
    return
true;
}
?>

Good luck!
majewsky at gmx dot net
27-Jun-2008 01:51
Paul: May it be that the ! operator is evaluated before the ===? In this case, the return value of strpos (0 in the described case) would be implicitly converted to bool (value true because 0 converts to false). Then, true === false is evaluated to false.
paul at thiswayupdesign dot co dot uk
18-Jun-2008 03:48
I wasn't aware of the !== operator, only the === for false. I was using this code on strpos:

while( ! ($start=@strpos($source,$startTag,$end)) === false)

This gave a false if the string was found at position 0, which is weird.

However using

while(($start=@strpos($source,$startTag,$end)) !== false)

Gives no such error and seems to work correctly
pawhox
26-May-2008 06:19
Hello! I was founding a function, which finds any occurence of a string (no: first occurence). I wasn't, so I maked this function! It may be very useful.

<?php

int strnpos
(string $haystack, mixed $needle, int $occurence);

?>

Example:

<?php

strnpos
("I like the bananas. You like coke. We like chocolate.", "like", 2); // 24

?>

Here's code of this function:

<?php

function strnpos($base, $str, $n)
    {       
        if (
$n <= 0 || intval($n) != $n || substr_count($base, $str) < $n)  return FALSE;
       
       
$str = strval($str);
       
$len = 0;
       
        for (
$i=0 ; $i<$n-1 ; ++$i)
        {
            if (
strpos($base, $str) === FALSE ) return FALSE;
           
           
$len += strlen( substr($base, 0, strpos($base, $str) + strlen($str)) );
           
           
$base = substr($base, strpos($base, $str) + strlen($str) );
        }
        return
strpos($base, $str) + $len;
    }

?>
ilaymyhat-rem0ve at yahoo dot com
01-Apr-2008 05:17
This might be useful.

class String{
   
    //Look for a $needle in $haystack in any position
    public static function contains(&$haystack, &$needle, &$offset)
    {
        $result = strpos($haystack, $needle, $offset);
        return $result !== FALSE;
    }
   
    //intuitive implementation .. if not found returns -1.
    public static function strpos(&$haystack, &$needle, &$offset)
    {
        $result = strpos($haystack, $needle, $offset);
        if ($result === FALSE )
        {
            return -1;
        }
        return $result;
    }
   
}//String
loaded67 at hotmail dot com
20-Feb-2008 07:08
Refereing to my last note.
It wasn't correct! As ctype_digit only evaluates strings.

(string) true / false will still be 0 / 1.

is_int(); is the correct function!
loaded67 at hotmail dot com
17-Feb-2008 10:22
As mentioned before....

0 === false
0 == false
1 === true
etc...

I found it very usefull to use ctype_digit(); with this function!

<?php
$string
= 'whatever!#%@^% is going on...'; //correct
//$string = 'whatever? is going on...'; //false char 8

//ctype_digit only works on strings so type cast...
if(ctype_digit((string) strpos($string, '?'))){
    echo
'found at least one...<br/>'.PHP_EOL;
}
else{
    echo
'no char index retrieved... <br/>'.PHP_EOL;
}
?>
amendment to last post on pink WARNING
11-Jan-2008 04:02
There's actually a fourth conceivable test for "any position other than 0" --

ADD:

!= ""  (disrecommended as highly confusing)

This then makes the final paragraph inaccurate (one case where comparing to "" is meaningful). It should just be removed entirely -- too much unneeded detail on a tangent anyway.
Suggested re-write for pink WARNING box
11-Jan-2008 03:45
WARNING

As strpos may return either FALSE (substring absent) or 0 (substring at start of string), strict versus loose equivalency operators must be used very carefully.

To know that a substring is absent, you must use: 

=== FALSE

To know that a substring is present (in any position including 0), you can use either of:

!== FALSE  (recommended)
 > -1  (note: or greater than any negative number)

To know that a substring is at the start of the string, you must use: 

=== 0

To know that a substring is in any position other than the start, you can use any of:

 > 0  (recommended)
!= 0  (note: but not !== 0 which also equates to FALSE)
!= FALSE  (disrecommended as highly confusing)

Also note that you cannot compare a value of "" to the returned value of strpos. With a loose equivalence operator (== or !=) it will return results which don't distinguish between the substring's presence versus position. With a strict equivalence operator (=== or !==) it will always return false.
Lau
24-Dec-2007 04:45
WARNING: The documentation says:
   "Use the === operator for testing the return value of this function"
but it should say:
    "Use '!== false' or '=== false' for testing the return value of this function"
   
Therefore to test if a needle occurst in a hastack do this:

if ( strpos($haystack, $needle) !== false){
     echo 'found needle in haystack!';
}    

Using '=== true' or '!== true' or '== true' or '== false' will all return the wrong value when the needle is found in the haystack.
using ' >= 0 ' returns the wrong value when the needle is not found in the haystack.

By "wrong value" I mean a value that is counter-intuitive but is never-the-less correct according to the weird way in which strpos has been coded. Why on earth didn't they just return -1 if the needle was not found? Then we could just test for >= 0

Here's a full list of the value returned:
(strpos("bbb", "aaa") >= 0)      returns true  EXPECTED FALSE
(strpos("bbb", "aaa") == true)   returns false expected false
(strpos("bbb", "aaa") == false)  returns true  expected true
(strpos("bbb", "aaa") === true)  returns false expected false
(strpos("bbb", "aaa") === false) returns true  expected true
(strpos("bbb", "aaa") !== false) returns false expected false
(strpos("bbb", "aaa") !== true)  returns true  expected true

(strpos("aaa", "aaa") >= 0)      returns true  expected true
(strpos("aaa", "aaa") == true)   returns false EXPECTED TRUE
(strpos("aaa", "aaa") == false)  returns true  EXPECTED FALSE
(strpos("aaa", "aaa") === true)  returns false EXPECTED TRUE
(strpos("aaa", "aaa") !== false) returns true  expected true
(strpos("aaa", "aaa") === false) returns false expected false
(strpos("aaa", "aaa") !== true)  returns true  EXPECTED FALSE
giulioNOSPAM at iunknown dot org
31-Oct-2007 03:19
A further implementation of the great rstrpos function posted in this page. Missing some parameters controls, but the core seems correct.

<?php
// Parameters:
//
// haystack : target string
// needle   : string to search
// offset   : which character in haystack to start searching, FROM THE END OF haystack
// iNumOccurrence : how many needle to search into haystack beginning from offset ( i.e. the 4th occurrence of xxx into yyy )

function rstrpos ($haystack, $needle, $offset=0, $iNumOccurrence=1)
  {
 
//
 
$size = strlen ($haystack);
 
$iFrom = $offset;
 
$iLoop = 0;
 
//
 
do
    {
   
$pos = strpos (strrev($haystack), strrev($needle), $iFrom);
   
$iFrom = $pos + strlen($needle);
    }
  while ((++
$iLoop)<$iNumOccurrence);
 
//
 
if($pos === false) return false;
 
//
 
return $size - $pos - strlen($needle);
  }
?>
Benjie
14-Oct-2007 04:49
str_replace evaluates its arguments exactly once.

for example:

<?php
$page
= str_replace("##randompicture##", getrandompicture(), $page);
?>

will call getrandompicture() once, ie it will insert the same random picture for each occurrence of ##randompicture## :(

Here is my quick and dirty workaround:

<?php
function add_random_pictures($text) {

  while ((
$i = strpos($text, "##randompicture##")) !== false) {
   
$text = substr_replace($text, getrandompicture(), $i, strlen("##randompicture##"));
  }
  return
$text;

}

$page = add_random_pictures($page);
?>
HS_AT_Duijst_DOT_com
09-Sep-2007 02:51
Just to be clear: unlike stripos(), strpos() is case-sensitive.
Cybertinus
28-Aug-2007 04:05
@Wagner Christian:

Yes, there are better methods. The best is to just cast is. You cast like this:
<?php
$id
= 1;
$string = (string) $id;
?>

If you var_dump() $string now you get the following output:
string(1) "1"

This is the recommended method. You're example should look like this then:
<?php
$id 
= 1;
$my_text = "hel124lo";
$first_position =strpos($my_text , (string) $id);
?>
Wagner Christian
17-Aug-2007 01:11
If you plan to use an integer as needle you need first to convert your integer into a String else it's not going to work.

For exemple :
<?php
$id 
= 1;
$my_text = "hel124lo";
$first_position =strpos($my_text ,substr($id,0));
?>

There are for sure some another solutions to convert an integer into a string in php.
user at nomail dot com
15-May-2007 02:21
This is a bit more useful when scanning a large string for all occurances between 'tags'.

<?php
function getStrsBetween($s,$s1,$s2=false,$offset=0) {
   
/*====================================================================
    Function to scan a string for items encapsulated within a pair of tags

    getStrsBetween(string, tag1, <tag2>, <offset>

    If no second tag is specified, then match between identical tags

    Returns an array indexed with the encapsulated text, which is in turn
    a sub-array, containing the position of each item.

    Notes:
    strpos($needle,$haystack,$offset)
    substr($string,$start,$length)

    ====================================================================*/

   
if( $s2 === false ) { $s2 = $s1; }
   
$result = array();
   
$L1 = strlen($s1);
   
$L2 = strlen($s2);

    if(
$L1==0 || $L2==0 ) {
        return
false;
    }

    do {
       
$pos1 = strpos($s,$s1,$offset);

        if(
$pos1 !== false ) {
           
$pos1 += $L1;

           
$pos2 = strpos($s,$s2,$pos1);

            if(
$pos2 !== false ) {
               
$key_len = $pos2 - $pos1;

               
$this_key = substr($s,$pos1,$key_len);

                if( !
array_key_exists($this_key,$result) ) {
                   
$result[$this_key] = array();
                }

               
$result[$this_key][] = $pos1;

               
$offset = $pos2 + $L2;
            } else {
               
$pos1 = false;
            }
        }
    } while(
$pos1 !== false );

    return
$result;
}
?>
Rich Deeson
26-Apr-2007 08:58
Here's a somewhat more efficient way to truncate a string at the end of a word. This will end the string on the last dot or last space, whichever is closer to the cut off point. In some cases, a full stop may not be followed by a space eg when followed by a HTML tag.

<?php
    $shortstring
= substr($originalstring, 0, 400);
   
$lastdot = strrpos($shortstring, ".");
   
$lastspace = strrpos($shortstring, " ");
   
$shortstring = substr($shortstring, 0, ($lastdot > $lastspace? $lastdot : $lastspace));
?>

Obviously, if you only want to split on a space, you can simplify this:

<?php
    $shortstring
= substr($originalstring, 0, 400);
   
$shortstring = substr($shortstring, 0, strrpos($shortstring, " "));
?>
14-Apr-2007 07:18
Thanks to spinicrus (see above) I have sorted out a problem that was bugging me for ages. I have a routine in Etomite Content Management System that will display a set number of characters of a news item and invite visitors to "Read more".

Unfortunately the 400 character summary sometimes displayed a partial word at the end.

Using the following code based on spinicrus's exampleI have now overcome this.

#################################
#only full word at the end
    $string=$rest;
    $charToFind=" ";
    $searchPos = $lentoshow;
    $searchChar = '';
    //
    while ($searchChar != $charToFind) {
        $newPos = $searchPos-1;
        $searchChar = substr($string,$newPos,strlen($charToFind));
        $searchPos = $newPos;
    }
$rest=substr($string,0,$searchPos)." ";
################################
sinai [at] simnet [dot] is
11-Apr-2007 05:35
If you want to check for either IE6 or 7 individually.

<?php

function browserIE($version)
{
  if(
$version == 6 || $version == 7)
  {
   
$browser = strpos($_SERVER['HTTP_USER_AGENT'], "MSIE ".$version.".0;");
          
    if(
$browser == true)
    {
      return
true;
    }
    else
    {
      return
false;
    }
  else
  {
    return
false;
}

?>
gal_chen123 at hotmail dot co dot il
03-Apr-2007 09:57
this function returns the text between 2 strings:

function get_between ($text, $s1, $s2) {
    $mid_url = "";
    $pos_s = strpos($text,$s1);
    $pos_e = strpos($text,$s2);
    for ( $i=$pos_s+strlen($s1) ; ( ( $i < ($pos_e)) && $i < strlen($text) ) ; $i++ ) {
        $mid_url .= $text[$i];
    }
    return $mid_url;
}

if $s1 or $s2 are not found, $mid_url will be empty
to add an offset, simply compare $pos_s to the offset, and only let it continue if the offset is smaller then $pos_s.
IcEye
25-Jan-2007 11:23
Get text between $s1 and $s2, return an array contains every occurrence (based on code of old comment/s but with offset and without strtolower)

Sample:
$myDivsContent = getStrsBetween("<div","</div>",$myHtmlSrc);

Sample:
or...get rows for html table
...
...
//using TextBetween from old comment...
$aTable = TextBetween("<table","</table>",$myHtmlSrc);
$rows = getStrsBetween("<tr","</tr>",$aTable);
...
...

function getStrsBetween($s1,$s2,$s,$offset=0){
  $result = array();
  $index= 0;
  $L1 = strlen($s1);
  $found = false;
  do{
    if($L1>0){
        $pos1 = strpos($s,$s1,$offset);
    }
    else {
        $pos1=$offset;
    }
    if($pos1 !== false){
        if($s2 == '')
            $result[$index++]= substr($s,$pos1+$L1);
        $pos2 = strpos(substr($s,$pos1+$L1),$s2,$L1);
        if($pos2!==false){
            $result[$index++]= substr($s,$pos1+$L1,$pos2);
            $offset += $pos2 + strlen($s2);
        }
        else{
            $pos1 = false;
        }   
    }
  }while($pos1 !== false);
  return $result;
}
 

BUGs/Problems:
Function do not stop while $s1 is found in $s.
jamie at jamiechong dot ca
19-Jan-2007 12:15
Try this function to find the first position of needle before a given offset.

For example:
<?php
$s
= "This is a test a is This";
$offset = strpos($s, "test");

strnpos($s, "is", $offset);  // returns 17
strnpos($s, "is", -$offset); // returns 5

// Works just like strpos if $offset is positive.
// If $offset is negative, return the first position of needle
// before before $offset.
function strnpos($haystack, $needle, $offset=0)
{
    if (
$offset>=0)
       
$result=strpos($haystack, $needle, $offset);
    else
    {
       
$offset=strlen($haystack)+$offset;
       
$haystack=strrev($haystack);
       
$needle=strrev($needle);
       
$result=strpos($haystack, $needle, $offset);
        if (
$result!==false)
        {
           
$result+=strlen($needle);
           
$result=strlen($haystack)-$result;
        }
    }
    return
$result;
}

?>
14-Jan-2007 04:52
this is nice you are so excited but parsing href=" will never really work.
remember whitespaces
mvp at mvpprograms dot com
29-Dec-2006 12:30
I understand the excitement of "admin at xylotspace dot com."  I wrote three functions that I use in EVERY website I develop.  What they do is get the text between strings.  I made them case-insensitive (for php < 5) using "strtolower." This would not be necessary if you used "stripos."  Now the first function is close to what "admin at xylotspace dot com" wrote, but does not have the position element.  It also will return an empty string if no substring was found.  If you want to get the title of an HTML document use:

 TextBetween('<title>','</title>',$content);

The second function was revolutionary for me, because it gets an array of items between pairs of strings.  So, with that I can grab most XML lists, or get all the links or images in a document.  All the links in a document could be found using:

 TextBetweenArray('href="','"',$content);

The third is less used, but is useful to process an array and get substrings within each record.

//-----GET TEXT BETWEEN STRINGS------
function TextBetween($s1,$s2,$s){
  $s1 = strtolower($s1);
  $s2 = strtolower($s2);
  $L1 = strlen($s1);
  $scheck = strtolower($s);
  if($L1>0){$pos1 = strpos($scheck,$s1);} else {$pos1=0;}
  if($pos1 !== false){
    if($s2 == '') return substr($s,$pos1+$L1);
    $pos2 = strpos(substr($scheck,$pos1+$L1),$s2);
    if($pos2!==false) return substr($s,$pos1+$L1,$pos2);
  }
  return '';
}

//-----GET ARRAY TEXT BETWEEN STRINGS------
function TextBetweenArray($s1,$s2,$s){
  $myarray=array();
  $s1=strtolower($s1);
  $s2=strtolower($s2);
  $L1=strlen($s1);
  $L2=strlen($s2);
  $scheck=strtolower($s);

  do{
  $pos1 = strpos($scheck,$s1);
  if($pos1!==false){
    $pos2 = strpos(substr($scheck,$pos1+$L1),$s2);
    if($pos2!==false){
      $myarray[]=substr($s,$pos1+$L1,$pos2);
      $s=substr($s,$pos1+$L1+$pos2+$L2);
      $scheck=strtolower($s);
      }
        }
  } while (($pos1!==false)and($pos2!==false));
  return $myarray;
}

//-----GET SUBTEXT IN ARRAY ITEMS------
function SubTextBetweenArray($s1,$s2,$myarray){
  for ($i=0; $i< count($myarray); $i++)
   {$myarray[$i]=TextBetween($s1,$s2,$myarray[$i]);}
  return $myarray;
}
koteskie at gmail dot com
18-Dec-2006 02:31
I've been looking at previous posts and came up with this function to find the start and end off an certain occurance or all occurances of needle within haystack.

I've made some minor tweaks to the code itself, like  counting the length of needle only once and counting the result set array instead of using a count variable.

I also added a length parameter to the result set to use in a following substr_replace call etc...

<?php

function strpos_index($haystack = '',$needle = '',$offset = 0,$limit = 99,$return = null)
{
   
$length = strlen($needle);
   
$occurances = array();
    while(((
$count = count($occurances)) < $limit) && (false !== ($offset = strpos($haystack,$needle,$offset))))
    {
       
$occurances[$count]['length'] = $length;
       
$occurances[$count]['start'] = $offset;
       
$occurances[$count]['end'] = $offset = $offset + $length;
    }
    return
$return === null ? $occurances : $occurances[$return];
}
       
?>
Charles
03-Dec-2006 12:10
Small improvement on the efforts of others:

<?php

function strpos_all($hs_haystack, $hs_needle, $hn_offset = 0, $hn_limit = 0) {
 
$ha_positions = array();
 
$hn_count = 0;

  while (
false !== ($pos = strpos($hs_haystack, $hs_needle, $hn_offset)) && ($hn_limit == 0 || $hn_count < $hn_limit)) {
   
$ha_positions[] = $pos;
   
$hn_offset = $pos + strlen($hs_needle);
    ++
$hn_count;
    }

  return
$ha_positions;
  }

function
preg_pos($hs_pattern, $hs_subject, &$hs_foundstring, $hn_offset = 0) {
 
$hs_foundstring = NULL;
    
  if (
preg_match($hs_pattern, $hs_subject, $ha_matches, PREG_OFFSET_CAPTURE, $hn_offset)) {
   
$hs_foundstring = $ha_matches[0][0];
    return
$ha_matches[0][1];
    }
  else {
    return
FALSE;
    }
  }

function
preg_pos_all($hs_pattern, $hs_subject, &$ha_foundstring, $hn_offset = 0, $hn_limit = 0) {
 
$ha_positions = array();
 
$ha_foundstring = array();
 
$hn_count = 0;

  while (
false !== ($pos = preg_pos($hs_pattern, $hs_subject, $hs_foundstring, $hn_offset)) && ($hn_limit == 0 || $hn_count < $hn_limit)) {
   
$ha_positions[] = $pos;
   
$ha_foundstring[] = $hs_foundstring;
   
$hn_offset = $pos + 1;                     // alternatively: '$pos + strlen($hs_foundstring)'
   
++$hn_count;
    }

  return
$ha_positions;
  }

print_r(preg_pos_all('/s...s/', "she sells sea shells on the sea floor", $ha_matches));
print_r($ha_matches);

?>
spinicrus at gmail dot com
14-Oct-2006 10:58
if you want to get the position of a substring relative to a substring of your string, BUT in REVERSE way:

<?php

function strpos_reverse_way($string,$charToFind,$relativeChar) {
   
//
   
$relativePos = strpos($string,$relativeChar);
   
$searchPos = $relativePos;
   
$searchChar = '';
   
//
   
while ($searchChar != $charToFind) {
       
$newPos = $searchPos-1;
       
$searchChar = substr($string,$newPos,strlen($charToFind));
       
$searchPos = $newPos;
    }
   
//
   
if (!empty($searchChar)) {
       
//
       
return $searchPos;
        return
TRUE;
    }
    else {
        return
FALSE;
    }
   
//
}

?>
admin at xylotspace dot com
26-Sep-2006 07:33
Yay! I came up with a very useful function. This finds a beginning marker and an ending marker (the first after the beginning marker), and returns the contents between them. You specify an initial position in order to tell it where to start looking. You can use a while() or for() loop to get all occurence of a certain string within a string (for example, taking all hyperlinks in a string of HTML code)...

function get_middle($source, $beginning, $ending, $init_pos) {
    $beginning_pos = strpos($source, $beginning, $init_pos);
    $middle_pos = $beginning_pos + strlen($beginning);
    $ending_pos = strpos($source, $ending, $beginning_pos + 1);
    $middle = substr($source, $middle_pos, $ending_pos - $middle_pos);
    return $middle;
}

For example, to find the URL of the very first hyperlink in an HTML string $data, use:

$first_url = get_middle($data, '<a href="', '"', 0);

It's done wonders for scraping HTML pages with certain tools on my website.
banana dot meal at gmail dot com
25-Aug-2006 06:07
To thepsion5 at hotmail dot com:

Please mind the warning part of the documentation!
Your function won't work on $Haystack s starting with $needle.

Here's a solution for that:
<?
function findAllOccurences($Haystack, $needle, $limit=0)
{
 
$Positions = array();
 
$currentOffset = 0;
 
$count=0;
  while((
$pos = strpos($Haystack, $needle, $offset))!==false && ($count < $limit || $limit == 0))
  {
  
$Positions[] = $pos;
  
$offset = $pos + strlen($needle);
  
$count++;
  }
  return
$Positions;
}
?>
spam at robkohr dot com
10-Aug-2006 12:38
Simple function to determine if a needle occurs in a haystack

function is_substr($needle, $haystack){
        $pos = strpos($haystack, $needle);
 
        if ($pos === false) {
                return false;
        } else {
                return true;
        }
}
thepsion5 at hotmail dot com
07-Aug-2006 10:57
I created this little function based on the one posted by chasesan at gmail dot com; It find all occurences of a string within another string and returns their positions as an array:

<?PHP
function findAllOccurences($Haystack, $needle, $limit=0)
{
 
$Positions = array();
 
$currentOffset = 0;
 
$count=0;
  while((
$pos = strpos($Haystack, $needle, $offset)) && ($count < $limit || $limit == 0))
  {
   
$Positions[] = $pos;
   
$offset = $pos + strlen($needle);
   
$count++;
  }
  return
$Positions;
}
?>
I hope this helps someone :)
wolfeym38 at yahoo dot com
24-Jul-2006 11:24
I finally figured out how to use this function correctly (and efficiently) if you want to test for a needle that may start at the beginning of haystack, simply use

if (strpos($haystack, $needle) === 0)) {
  do stuff here..
}

someone else mentioned that you needed to assign a variable first and test to make sure that it was === true first.. That is not needed
wormss at wormss dot net
18-Jul-2006 05:26
Im sure there are more efficient methods of this, but i use this alot when dealing with rss and was proud of it.
<?
function data_from_element($needle,$haystack,$tags=FALSE) { // Expects two Strings, returns Array
   
$needle_start = "<".$needle.">"; $needle_end = "</".$needle.">";
   
$array = array();    $pos_start = 0;
    while((
$pos_start = strpos($haystack,$needle_start,$pos_start)) !== false) {
       
$pos_end = strpos($haystack,$needle_end,$pos_start);
        if(
$tags) $array[] = substr($haystack,$pos_start,$pos_end-$pos_start+strlen($needle_end));
        else
$array[] = substr($haystack,$pos_start + strlen($needle_start),$pos_end - $pos_start - strlen($needle_start));
       
$pos_start++;
    }
    return
$array;
}
d
//example
$rss = '<?xml version="1.0"?> <rss version="2.0"> <channel> <title>Example RSS</title> <description>Example RSS Description</description> <link>http://example.com/rss/</link> <item> <title>Example RSS 1</title> <link>http://example.com/rss/1.html</link> <description>Example 1</description> </item> <item> <title>Example RSS 2</title> <link>http://example.com/rss/2.html</link> <description>Example 2</description> </item> </channel> </rss>';

$items = data_from_elements(link,$rss); // $rss[0] => "http://example.com/rss/"
$items = data_from_elements(link,$rss,true); // $rss[0] => "<link> http://example.com/rss/ </link>"
?>
chasesan at gmail dot com
12-Jul-2006 03:48
You can use strpos to produce a funciton that will find the nth instance of a certain string within a string. Personally I find this function almost more useful then strpos itself.

I kinda wish they would put it stock into php but I doupt thats gonna happen any time soon. ^_^

Here is da code:
<?php
//just like strpos, but it returns the position of the nth instance of the needle (yay!)
function strpos2($haystack, $needle, $nth = 1)
{
   
//Fixes a null return if the position is at the beginning of input
    //It also changes all input to that of a string ^.~
   
$haystack = ' '.$haystack;
    if (!
strpos($haystack, $needle))
        return
false;
   
$offset=0;
    for(
$i = 1; $i < $nth; $i++)
       
$offset = strpos