strpos

(PHP 4, PHP 5)

strposSucht das erste Vorkommen des Suchstrings

Beschreibung

int strpos ( string $haystack , mixed $needle [, int $offset = 0 ] )

Gibt die numerische Position des ersten Vorkommens von needle innerhalb der Zeichenkette haystack zurück.

Parameter-Liste

haystack

Die Zeichenkette, in der gesucht werden soll.

needle

Ist needle kein String, wird der Parameter in einen Integerwert konvertiert, der dem Ordinalwert des Zeichens entspricht.

offset

Der optionale Parameter offset ermöglicht es Ihnen, die Startposition für die Suche innerhalb von haystack anzugeben. Die zurück gegebene Positions-Angabe ist dann relativ zum Anfang von haystack.

Rückgabewerte

Gibt die Position als Integerwert zurück. Wurde needle nicht gefunden, gibt strpos() den boolean-Wert FALSE zurück.

Warnung

Diese Funktion kann sowohl das boolsche FALSE zurückliefern, als auch einen nicht-boolschen Wert, welcher zu FALSE ausgewertet wird. Weitere Informationen entnehmen Sie bitte dem Abschnitt über die boolschen Typen. Benutzen Sie deshalb den === Operator, um den Rückgabewert dieser Funktion zu überprüfen.

Beispiele

Beispiel #1 Verwendung von ===

<?php
$meinString 
'abc';
$findMich   'a';
$pos strpos($meinString$findMich);

// Beachten Sie die Verwendung von ===. Ein einfacher Vergleich (==) liefert
// nicht das erwartete Ergebnis, da die Position von 'a' die nullte Stelle
// (also das erste Zeichen) ist
if ($pos === false) {
    echo 
"Der String '$findMich' wurde nicht im String '$meinString' gefunden";
} else {
    echo 
"Der String '$findMich' wurde im String '$meinString' gefunden";
    echo 
" und befindet sich an Position $pos";
}
?>

Beispiel #2 Verwendung von !==

<?php
$meinString 
'abc';
$findMich   'a';
$pos strpos($meinString$findMich);

// Der !==-Operator kann ebenfalls verwendet werden. Die Verwendung von != von
// != würde in unserem Beispiel nicht wie erwartet arbeiten, da die Position
// von 'a' 0 ist. Das Statement (0 != false) evaluiert hierbei zu false.
if ($pos !== false) {
    echo 
"Der String '$findMich' wurde im String '$meinString' gefunden";
    echo 
" und befindet sich an Position $pos";
} else {
    echo 
"Der String '$findMich' wurde nicht im String '$meinString' gefunden";
}
?>

Beispiel #3 Verwendung eines Offsets

<?php
// Wir koennen nach einem Zeichen suchen und dabei alles vor dem Offset ignorieren
$newstring 'abcdef abcdef';
$pos strpos($newstring'a'1); // $pos = 7, nicht 0
?>

Anmerkungen

Hinweis: Diese Funktion ist binary safe.

Siehe auch

  • strrpos() - Findet das letzte Vorkommen eines Zeichens innerhalb einer Zeichenkette
  • stripos() - Findet das erste Vorkommen eines Strings, unabhängig von Groß- und Kleinschreibung
  • strripos() - Findet das letzte Vorkommen der gesuchten Zeichenkette in einem String, unabhängig von Groß- und Kleinschreibung
  • strrchr() - Sucht das letzte Vorkommen eines Zeichens in einem String
  • substr() - Gibt einen Teil eines Strings zurück
  • stristr() - Wie strstr, aber unabhängig von Groß- bzw. Kleinschreibung
  • strstr() - Findet das erste Vorkommen eines Strings

add a note add a note

User Contributed Notes 40 notes

up
32
Suggested re-write for pink WARNING box
6 years ago
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.
up
5
qrworld.net
1 month ago
I found a function in this post http://softontherocks.blogspot.com/2014/11/buscar-multiples-textos-en-un-texto-con.html
that implements the search in both ways, case sensitive or case insensitive, depending on an input parameter.

The function is:

function getMultiPos($haystack, $needles, $sensitive=true, $offset=0){
    foreach($needles as $needle) {
        $result[$needle] = ($sensitive) ? strpos($haystack, $needle, $offset) : stripos($haystack, $needle, $offset);
    }
    return $result;
}

It was very useful for me.
up
6
teddanzig at yahoo dot com
5 years ago
routine to return -1 if there is no match for strpos

<?php
//instr function to mimic vb instr fucntion
function InStr($haystack, $needle)
{
   
$pos=strpos($haystack, $needle);
    if (
$pos !== false)
    {
        return
$pos;
    }
    else
    {
        return -
1;
    }
}
?>
up
9
akarmenia at gmail dot com
3 years ago
My version of strpos with needles as an array. Also allows for a string, or an array inside an array.

<?php
function strpos_array($haystack, $needles) {
    if (
is_array($needles) ) {
        foreach (
$needles as $str) {
            if (
is_array($str) ) {
               
$pos = strpos_array($haystack, $str);
            } else {
               
$pos = strpos($haystack, $str);
            }
            if (
$pos !== FALSE) {
                return
$pos;
            }
        }
    } else {
        return
strpos($haystack, $needles);
    }
}

// Test
echo strpos_array('This is a test', array('test', 'drive')); // Output is 10

?>
up
8
Achintya
5 years ago
A function I made to find the first occurrence of a particular needle not enclosed in quotes(single or double). Works for simple nesting (no backslashed nesting allowed).

<?php
function strposq($haystack, $needle, $offset = 0){
   
$len = strlen($haystack);
   
$charlen = strlen($needle);
   
$flag1 = false;
   
$flag2 = false;
    for(
$i = $offset; $i < $len; $i++){
        if(
substr($haystack, $i, 1) == "'"){
           
$flag1 = !$flag1 && !$flag2 ? true : false;
        }
        if(
substr($haystack, $i, 1) == '"'){
           
$flag2 = !$flag1 && !$flag2 ? true : false;
        }
        if(
substr($haystack, $i, $charlen) == $needle && !$flag1 && !$flag2){
            return
$i;       
        }
    }
    return
false;
}

echo
strposq("he'llo'character;\"'som\"e;crap", ";"); //16
?>
up
3
rjeggens at ijskoud dot org
2 years ago
I lost an hour before I noticed that strpos only returns FALSE as a boolean, never TRUE.. This means that

strpos() !== false

is a different beast then:

strpos() === true

since the latter will never be true. After I found out, The warning in the documentation made a lot more sense.
up
5
digitalpbk [at] gmail.com
5 years ago
This function raises a warning if the offset is not between 0 and the length of string:

Warning: strpos(): Offset not contained in string in %s on line %d
up
2
dale at ucsc dot edu
9 years ago
if you want need a fast function to find the first occurrence of any ch element of an needle array this function might be of use:
<?php
$eurl
= strpos_needle_array($text, array('"'=>0,'\''=>0,'>'=>0, ' '=>0, "\n"=>0), $surl);

function
strpos_needle_array(& $text, $needle_ary, $offset=0){   
    for(
$ch_pos=$offset;$ch_pos<strlen($text);$ch_pos++){
        if(isset(
$needle_ary[$text[$ch_pos]])){
            return
$ch_pos;
        }
    }
    return
false;
}
?>
up
1
mtroy dot student at gmail dot com
2 years ago
when you want to know how much of substring occurrences, you'll use "substr_count".
But, retrieve their positions, will be harder.
So, you can do it by starting with the last occurrence :

function strpos_r($haystack, $needle)
{
    if(strlen($needle) > strlen($haystack))
        trigger_error(sprintf("%s: length of argument 2 must be <= argument 1", __FUNCTION__), E_USER_WARNING);

    $seeks = array();
    while($seek = strrpos($haystack, $needle))
    {
        array_push($seeks, $seek);
        $haystack = substr($haystack, 0, $seek);
    }
    return $seeks;
}

it will return an array of all occurrences a the substring in the string

Example :

$test = "this is a test for testing a test function... blah blah";
var_dump(strpos_r($test, "test"));

// output

array(3) {
  [0]=>
  int(29)
  [1]=>
  int(19)
  [2]=>
  int(10)
}

Paul-antoine
Malézieux.
up
3
spinicrus at gmail dot com
8 years ago
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;
    }
   
//
}

?>
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2
gjh42 - simonokewode at hotmail dot com
3 years ago
A pair of functions to replace every nth occurrence of a string with another string, starting at any position in the haystack. The first works on a string and the second works on a single-level array of strings, treating it as a single string for replacement purposes (any needles split over two array elements are ignored).

Can be used for formatting dynamically-generated HTML output without touching the original generator: e.g. add a newLine class tag to every third item in a floated list, starting with the fourth item.

<?php
/* String Replace at Intervals   by Glenn Herbert (gjh42)    2010-12-17
*/

//(basic locator by someone else - name unknown)
//strnposr() - Find the position of nth needle in haystack.
function strnposr($haystack, $needle, $occurrence, $pos = 0) {
    return (
$occurrence<2)?strpos($haystack, $needle, $pos):strnposr($haystack,$needle,$occurrence-1,strpos($haystack, $needle, $pos) + 1);
}

//gjh42
//replace every nth occurrence of $needle with $repl, starting from any position
function str_replace_int($needle, $repl, $haystack, $interval, $first=1, $pos=0) {
  if (
$pos >= strlen($haystack) or substr_count($haystack, $needle, $pos) < $first) return $haystack;
 
$firstpos = strnposr($haystack, $needle, $first, $pos);
 
$nl = strlen($needle);
 
$qty = floor(substr_count($haystack, $needle, $firstpos + 1)/$interval);
  do {
//in reverse order
   
$nextpos = strnposr($haystack, $needle, ($qty * $interval) + 1, $firstpos);
   
$qty--;
   
$haystack = substr_replace($haystack, $repl, $nextpos, $nl);
  } while (
$nextpos > $firstpos);
  return
$haystack;
}
 
//$needle = string to find
  //$repl = string to replace needle
  //$haystack = string to do replacing in
  //$interval = number of needles in loop
  //$first=1 = first occurrence of needle to replace (defaults to first)
  //$pos=0 = position in haystack string to start from (defaults to first)

//replace every nth occurrence of $needle with $repl, starting from any position, in a single-level array
function arr_replace_int($needle, $repl, $arr, $interval, $first=1, $pos=0, $glue='|+|') {
  if (!
is_array($arr))  return $arr;
  foreach(
$arr as $key=>$value){
    if (
is_array($arr[$key])) return $arr;
  }
 
$haystack = implode($glue, $arr);
 
$haystack = str_replace_int($needle, $repl, $haystack, $interval, $first, $pos);
 
$tarr = explode($glue, $haystack);
 
$i = 0;
  foreach(
$arr as $key=>$value){
   
$arr[$key] = $tarr[$i];
   
$i++;
  }
  return
$arr;
}
?>
If $arr is not an array, or a multilevel array, it is returned unchanged.
up
3
Anonymous
1 year ago
The most straightforward way to prevent this function from returning 0 is:

  strpos('x'.$haystack, $needle, 1)

The 'x' is simply a garbage character which is only there to move everything 1 position.
The number 1 is there to make sure that this 'x' is ignored in the search.
This way, if $haystack starts with $needle, then the function returns 1 (rather than 0).
up
1
arias at elleondeoro dot com
9 years ago
If you want to get all positions in an array, you can use this function. If the optional parameter count is especified, the function will put there the number of matches.

<?php
function strallpos($pajar, $aguja, $offset=0, &$count=null) {
  if (
$offset > strlen($pajar)) trigger_error("strallpos(): Offset not contained in string.", E_USER_WARNING);
 
$match = array();
  for (
$count=0; (($pos = strpos($pajar, $aguja, $offset)) !== false); $count++) {
   
$match[] = $pos;
   
$offset = $pos + strlen($aguja);
  }
  return
$match;
}
?>
up
2
ilaymyhat-rem0ve at yahoo dot com
6 years ago
This might be useful.

<?php
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
?>
up
1
olmstead31 at yahoo dot com
4 years ago
I found that whatever I was using as a test with strpos it came out false exept if $pos was == 1

I figured it gives me a numeric value if found else it is null or false
here is what i did to make my code work:

<?php
//EXAMPLE 1:
$quiamime = ',64,68,70,';
$me = '64'
$posi = strpos($quiaime, ",$me,");  //posi is equal to 0
if (!is_numeric($posi)){
//code here
}else{
 
//else code here
}

//EXAMPLE 2:
$quiamime = ',68,70,64,';
$me = '64'
$posi = strpos($quiaime, ",$me,");  //posi is equal to 6
if (!is_numeric($posi)){
//code here
}else{
 
//else code here
}

//EXAMPLE 3:
$quiamime = ',68,70,';
$me = '64'
$posi = strpos($quiaime, ",$me,");  //posi is equal to NULL or FALSE
if (!is_numeric($posi)){
//code here
}else{
 
//else code here
}
?>
up
1
yasindagli at gmail dot com
5 years ago
This function finds postion of nth occurence of a letter starting from offset.

<?php
function nth_position($str, $letter, $n, $offset = 0){
   
$str_arr = str_split($str);
   
$letter_size = array_count_values(str_split(substr($str, $offset)));
    if( !isset(
$letter_size[$letter])){
       
trigger_error('letter "' . $letter . '" does not exist in ' . $str . ' after ' . $offset . '. position', E_USER_WARNING);
        return
false;
    } else if(
$letter_size[$letter] < $n) {
       
trigger_error('letter "' . $letter . '" does not exist ' . $n .' times in ' . $str . ' after ' . $offset . '. position', E_USER_WARNING);
        return
false;
    }
    for(
$i = $offset, $x = 0, $count = (count($str_arr) - $offset); $i < $count, $x != $n; $i++){
        if(
$str_arr[$i] == $letter){
           
$x++;
        }
    }
    return
$i - 1;
}

echo
nth_position('foobarbaz', 'a', 2); //7
echo nth_position('foobarbaz', 'b', 1, 4); //6
?>
up
1
Tim
6 years ago
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;
    }
}
?>
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1
user at nomail dot com
7 years ago
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;
}
?>
up
1
ah dot d at hotmail dot com
5 years ago
A strpos modification to return an array of all the positions of a needle in the haystack

<?php
function strallpos($haystack,$needle,$offset = 0){
   
$result = array();
    for(
$i = $offset; $i<strlen($haystack); $i++){
       
$pos = strpos($haystack,$needle,$i);
        if(
$pos !== FALSE){
           
$offset $pos;
            if(
$offset >= $i){
               
$i = $offset;
               
$result[] = $offset;
            }
        }
    }
    return
$result;
}
?>

example:-

<?php
$haystack
= "ASD is trying to get out of the ASDs cube but the other ASDs told him that his behavior will destroy the ASDs world";

$needle = "ASD";

print_r(strallpos($haystack,$needle));

//getting all the positions starting from a specified position

print_r(strallpos($haystack,$needle,34));
?>
up
1
bishop
10 years ago
Code like this:
<?php
if (strpos('this is a test', 'is') !== false) {
    echo
"found it";
}
?>

gets repetitive, is not very self-explanatory, and most people handle it incorrectly anyway. Make your life easier:

<?php
function str_contains($haystack, $needle, $ignoreCase = false) {
    if (
$ignoreCase) {
       
$haystack = strtolower($haystack);
       
$needle   = strtolower($needle);
    }
   
$needlePos = strpos($haystack, $needle);
    return (
$needlePos === false ? false : ($needlePos+1));
}
?>

Then, you may do:
<?php
// simplest use
if (str_contains('this is a test', 'is')) {
    echo
"Found it";
}

// when you need the position, as well whether it's present
$needlePos = str_contains('this is a test', 'is');
if (
$needlePos) {
    echo
'Found it at position ' . ($needlePos-1);
}

// you may also ignore case
$needlePos = str_contains('this is a test', 'IS', true);
if (
$needlePos) {
    echo
'Found it at position ' . ($needlePos-1);
}
?>
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1
ohcc at 163 dot com
5 months ago
Be careful when the $haystack or $needle parameter is an integer.
If you are not sure of its type, you should  convert it into a string.
<?php
    var_dump
(strpos(12345,1));//false
   
var_dump(strpos(12345,'1'));//0
   
var_dump(strpos('12345',1));//false
   
var_dump(strpos('12345','1'));//0
   
$a = 12345;
   
$b = 1;
   
var_dump(strpos(strval($a),strval($b)));//0
   
var_dump(strpos((string)$a,(string)$b));//0   
?>
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1
andrew dot macrobert+php at gmail dot com
6 months ago
This function finds ALL occurrences of a substring, returning an array of indexes referring to the start of each occurrence. Overlapping subtrings are not included.
<?php
function strpos_all($haystack, $needle) {
 
$instances = array();

 
$offset = 0;
  while((
$offset = strpos($haystack, $needle, $offset)) !== FALSE) {
   
$instances[] = $offset;
   
$offset += strlen($needle);
  }

  return
$instances;
}
?>
up
0
Andres
5 months ago
strpos: Want to find lines in text file, NOT beginning with a comment (// for example)?
That way it Works:
$komm=strpos($var,'//');
if($komm === FALSE || $komm == TRUE){}

Generally, it is a nonsense. Why 'strpos' cant ALWAYS output an integer?
up
0
mail at nikha dot org
6 months ago
What the manual says about "if $needle is not a string" is confusing.

in fact, strpos() compares strings, and nothing else.

Example:
$haystack = "123456789";

$needle = 2;
strpos($haystack, $needle) returns boolean false
$needle = "2";
strpos($haystack, $needle) returns 1;

My real life problem were timestamps. I had a list of timestamps like this: "!<timestamp0>!<timestamp1>!<timestamp2>..." Then I tried to find out, wheter an actualy by "mktime()" generated timestamp is found in this list or not. But strpos() returned always boolean 0, because mktime() results are integers.

It worked only like this:
strpos($timestamp_list, strval($mktime_result))

may be helpfull for others...
Niklaus
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binodluitel at hotmail dot com
8 months ago
This function will return 0 if the string that you are searching matches i.e. needle matches the haystack

{code}
echo strpos('bla', 'bla');
{code}

Output: 0
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0
m at binh dot vn
9 months ago
Using strpos can be tricky sometimes. To reuse it for one search you can use this form:

<?php
$found
= (strpos($haystack, $needle) !== false);
?>

For example:

<?php
$url
= "http://www.binh.vn";
$found = (strpos($url, 'http') !== false);
if (
$found) echo "Found http";
?>

Clearly we see that the position will be 0 but the $found will be true and so we can use more than one time of if ($found) which is much easier.

To further reuse it we could make a very short function:
<?php
function found($haystack, $needle) {
  return (
strpos($haystack, $needle) !== false);
}
?>

Wonder why php didn't have such function for easier use?
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0
harshitpatelrock25 at gmail dot com
1 year ago
TO find the position specific word in a para:-

<?php
  $String
= 'This is the php language And is Used to develop web programs';
 
$find = '1232';
 
$find_leg = strlen($find);
 
$start_pos = 00;
 
  while(
$string_pos = strpos($String,$find,$start_pos)){
      echo
"<strong> \" $find \" </strong> was found on position : $string_pos <br>" ;
    
$start_pos = $string_pos + $find_leg;
  }
?>
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0
Lurvik
1 year ago
Don't know if already posted this, but if I did this is an improvement.

This function will check if a string contains  a needle. It _will_ work with arrays and multidimensional arrays (I've tried with a > 16 dimensional array and had no problem).

<?php
function str_contains($haystack, $needles)
{
   
//If needles is an array
   
if(is_array($needles))
    {
       
//go trough all the elements
       
foreach($needles as $needle)
        {
           
//if the needle is also an array (ie needles is a multidimensional array)
           
if(is_array($needle))
            {
               
//call this function again
               
if(str_contains($haystack, $needle))
                {
                   
//Will break out of loop and function.
                   
return true;
                }
               
                return
false;
            }

           
//when the needle is NOT an array:
                //Check if haystack contains the needle, will ignore case and check for whole words only
           
elseif(preg_match("/\b$needle\b/i", $haystack) !== 0)
            {
                return
true;
            }
        }
    }
   
//if $needles is not an array...
   
else
    {
        if(
preg_match("/\b$needles\b/i", $haystack) !== 0)
        {
            return
true;
        }
    }

    return
false;
}
?>
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0
kiipa at live dot com
1 year ago
So I needed a function to check if a string contains a string. But that also works with arrays. And multidimensional arrays.

Well commented, because I'm sharing the source I use this in.

<?php
private static $found;
//Sees if a string contains another string, WORKS WITH 2D ARRAYS! Returns true or false.
public static function strcont($haystack, $needles)
{
   
//If needles is an array
   
if(is_array($needles))
    {
       
//go trough all the elements
       
foreach($needles as $needle)
        {
           
//if the needle is also an array (ie needles is a multidimensional array)
           
if(is_array($needle))
            {
               
//call this function again
               
static::strcont($haystack, $needle);
            }
           
//when the needle is NOT an array:
           
elseif(strpos($haystack, $needle) !== false)
            {
               
//Set the bool to true (DO NOT CHANGE TO return true). IT WILL NOT WORK!
               
static::$found = true;
            }
        }

       
//Because we only set the bool if we found something we'll check if the bool is set.
       
if(isset(static::$found))
        {
           
//Then return true.
           
return true;
        }
       
        return
false;
    }
   
//If the needles is not an array (this function can be used as strpos...)
   
else
    {
        if(
strpos($haystack, $needles) !== false)
        {
            return
true;
        }
       
        return
falsE;
    }
}   
?>
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martijn at martijnfrazer dot nl
2 years ago
This is a function I wrote to find all occurrences of a string, using strpos recursively.

<?php
function strpos_recursive($haystack, $needle, $offset = 0, &$results = array()) {               
   
$offset = strpos($haystack, $needle, $offset);
    if(
$offset === false) {
        return
$results;           
    } else {
       
$results[] = $offset;
        return
strpos_recursive($haystack, $needle, ($offset + 1), $results);
    }
}
?>

This is how you use it:

<?php
$string
= 'This is some string';
$search = 'a';
$found = strpos_recursive($string, $search);

if(
$found) {
    foreach(
$found as $pos) {
        echo
'Found "'.$search.'" in string "'.$string.'" at position <b>'.$pos.'</b><br />';
    }   
} else {
    echo
'"'.$search.'" not found in "'.$string.'"';
}
?>
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jim at terrys dot net
3 years ago
strpos that accepts an array for $needle

<?php
// strpos that takes an array of values to match against a string
// note the stupid argument order (to match strpos)
function strpos_arr($haystack, $needle) {
    if(!
is_array($needle)) $needle = array($needle);
    foreach(
$needle as $what) {
        if((
$pos = strpos($haystack, $what))!==false) return $pos;
    }
    return
false;
}
?>
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gambajaja at yahoo dot com
4 years ago
<?php
$my_array
= array ('100,101', '200,201', '300,301');
$check_me_in = array ('100','200','300','400');
foreach (
$check_me_in as $value_cmi){
   
$is_in=FALSE; #asume that $check_me_in isn't in $my_array
   
foreach ($my_array as $value_my){
       
$pos = strpos($value_my, $value_cmi);
        if (
$pos===0)
           
$pos++;
        if (
$pos==TRUE){
           
$is_in=TRUE;
           
$value_my2=$value_my;
            }
    }
    if (
$is_in) echo "ID $value_cmi in \$check_me_in I found in value '$value_my2' \n";
}
?>

The above example will output
ID 100 in $check_me_in I found in value '100,101'
ID 200 in $check_me_in I found in value '200,201'
ID 300 in $check_me_in I found in value '300,301'
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usulaco at gmail dot com
4 years ago
Parse strings between two others in to array.

<?php
function g($string,$start,$end){
    
preg_match_all('/' . preg_quote($start, '/') . '(.*?)'. preg_quote($end, '/').'/i', $string, $m);
    
$out = array();

     foreach(
$m[1] as $key => $value){
      
$type = explode('::',$value);
       if(
sizeof($type)>1){
          if(!
is_array($out[$type[0]]))
            
$out[$type[0]] = array();
         
$out[$type[0]][] = $type[1];
       } else {
         
$out[] = $value;
       }
     }
  return
$out;
}
print_r(g('Sample text, [/text to extract/] Rest of sample text [/WEB::http://google.com/] bla bla bla. ','[/','/]'));
?>

results:
Array
(
    [0] => text to extract
    [WEB] => Array
        (
            [0] => http://google.com
        )

)

Can be helpfull to custom parsing :)
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jburns131 at jbwebware dot com
5 years ago
The Situation:

I wanted to return TRUE if strpos returned position 0, and only position 0, without the added overhead of preg_match.

The Solution:

As PHP treats 0 (zero) as NULL, and strpos returns the int 0 (but not NULL), I used type casting and the "===" comparison operator (as it compares types) to resolve my issue.

<?php

$hayStack
= "dbHost";
$needle  = "db"
$needlePos = strpos($hayStack, $needle);

if((string)
$needlePos === (string)0) {
    echo
"db is in position zero";
} else {
    echo
"db is NOT in position zero";
}

?>

Returns:
db is in position zero

<?php

$hayStack
= "another_db_host";
$needle  = "db"
$needlePos = strpos($hayStack, $needle);

if((string)
$needlePos === (string)0) {
    echo
"db is in position zero";
} else {
    echo
"db is NOT in position zero";
}

?>

This returns:
db is in NOT position zero
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mickRacky
6 years ago
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
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paul at thiswayupdesign dot co dot uk
6 years ago
I wasn't aware of the !== operator, only the === for false. I was using this code on strpos:

<?php
while( ! ($start=@strpos($source,$startTag,$end)) === false) {
 
// ...
}
?>

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

However using

<?php
while(($start=@strpos($source,$startTag,$end)) !== false) {
 
// ...
}
?>

Gives no such error and seems to work correctly
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gal_chen123 at hotmail dot co dot il
7 years ago
this function returns the text between 2 strings:

<?php
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 $pos_s.
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philip
10 years ago
Many people look for in_string which does not exist in PHP, so, here's the most efficient form of in_string() (that works in both PHP 4/5) that I can think of:
<?php
function in_string($needle, $haystack, $insensitive = false) {
    if (
$insensitive) {
        return
false !== stristr($haystack, $needle);
    } else {
        return
false !== strpos($haystack, $needle);
    }
}
?>
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-1
daevid at daevid dot com
4 years ago
Dan Brown and I had a discussion on the PHP list about the speed difference between the popular three string searching techniques. He wrote a simple timing test, and I adapted it further. The end result is that all three are very close and not even noticeable for sets < 1M. Although, technically strpos() is about twice as fast (as the docs allude to above). Here it is for your own amusement and testing purposes.

<?php
for ($i = 0; $i < 1000000; $i++ )
   
$o[] =
sprintf('%04d-%02d-%02d',rand(0000,9999),rand(00,99),rand(00,99));
#print_r($o);
echo "array of ".number_format($i)."\n";
###################################################################
$now = microtime(true);
for(
$i=0;$i<count($o);$i++) {
       if(
preg_match('/^[0]{4,}\-/U',$o[$i])) {
              
//echo "Offset #".$i." matches: ".$o[$i].PHP_EOL;
      
}
}
$rank['preg_match'] = (microtime(true) - $now);
###################################################################
$later = microtime(true);
for(
$i=0;$i<count($o);$i++) {
        if(
substr($o[$i],0,4) == "0000") {
               
//echo "Offset #".$i." matches: ".$o[$i].PHP_EOL;
       
}
}
$rank['substr'] = (microtime(true) - $later);
###################################################################
$after = microtime(true);
for(
$i=0;$i<count($o);$i++) {
        if(
strpos($o[$i], '0000') === 0) {
               
//echo "Offset #".$i." matches: ".$o[$i].PHP_EOL;
       
}
}
$rank['strpos'] = (microtime(true) - $after);
###################################################################
asort($rank);
print_r($rank);
?>

array of 10,000
Array
(
    [strpos] => 0.00766682624817
    [substr] => 0.0116670131683
    [preg_match] => 0.0124950408936
)

array of 100,000
Array
(
    [strpos] => 0.0817799568176
    [substr] => 0.120522975922
    [preg_match] => 0.125612974167
)

array of 1,000,000
Array
(
    [strpos] => 0.805890083313
    [substr] => 1.19799995422
    [preg_match] => 1.25615906715
)

I ran out of memory with more than 1M array elements.
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Anonymous
4 years ago
Beware the mindless "if needle is not string":

# php -r 'var_dump(strpos("X1234567",5));'
bool(false)
# php -r 'var_dump(strpos("X1234567","5"));'
int(5)
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