PHP: strpos - Manual

strpos

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++)

        $offset = strpos($haystack, $needle, $offset) + 1;

    return strpos($haystack, $needle, $offset) - 1;

}

?>

steve at webcommons dot biz
05-Jul-2006 11:56


If you're wanting a simple "strpos" using a pattern and don't need the complexity of multi_strpos below, this function (for PHP 4.3.0+) returns the regex position.



  function preg_pos($sPattern, $sSubject, &$FoundString, $iOffset = 0) {

      $FoundString = NULL;

      

      if (preg_match($sPattern, $sSubject, $aMatches, PREG_OFFSET_CAPTURE, $iOffset) > 0) {

        $FoundString = $aMatches[0][0];

        return $aMatches[0][1];

      }

      else {

        return FALSE;

      }

  }



It also returns the actual string found using the pattern, via $FoundString.

ludvig dot ericson at gmail dot com
27-Apr-2006 01:28


As a simplified way of doing what the poster below did:



<?php

$firstName .= '\'';

if (!preg_match('/[sx]$/', $firstName)) {

    $firstName .= 's';

}

?>



If you feel using a regular expression is too much, try it - I've not tested yet, but I'd say preg_match() is faster then two strpos() calls.

leibwaechter at web dot de
23-Mar-2006 01:26


If you only want to look, if a string appears in another string - even at position 0 - , you can also use substr_count():



<?php

  $mystring = "Hello Chris";



  if (substr_count($mystring, "Hello") == 0)

    echo "no";



  // same as:



  if (strpos($mystring, "Hello") === false)

    echo "no";

?>

arachnion at gmail dot com
04-Mar-2006 10:17


<?php

//use a string as needle, even in PHP 4

//works the same like strrpos()

function stringrpos( $sHaystack, $sNeedle )

{

  $i = strlen( $sHaystack );

  while ( substr( $sHaystack, $i, strlen( $sNeedle ) ) != $sNeedle )

  {

    $i--;

    if ( $i < 0 )

    {

      return false;

    }

  }

  return $i;

}

?>

18-Feb-2006 03:48


this works fine:



function getCurrentBrowser() {

    $browser = $_SERVER['HTTP_USER_AGENT'];

    

    if (strpos(strtoupper($browser), 'MSIE') !== false) {    

        return "Internet Explorer";

    } else     if (strpos(strtoupper($browser), 'FIREFOX') !== false) {

        return "Firefox";

    } else     if (strpos(strtoupper($browser), 'KONQUEROR') !== false) {

        return "Konqueror";

    } else     if (strpos(strtoupper($browser), "LYNX") !== false) {

        return "Lynx";

    } else {    

        return $browser;

    }

}



if $browser ist

"Lynx/2.8.5rel.2 libwww-FM/2.14 SSL-MM/1.4.1 OpenSSL/0.9.7g"

its work fine, too.

php /at/ da.mcbf.net
15-Feb-2006 07:49


"fox_galih at yahoo dot co dot uk" example below is absolutely not needed. As the example on this page shows, you can differentiate between position 0 and false by doing a strict comparison (===):



$newsbody = "<p>This is paragraph</p>";



if( strpos( $newsbody, "<p>" ) === 0 ) {

   // will only get executed if string starts with <p>

   // (false === 0) evaluates to false

}

fox_galih at yahoo dot co dot uk
11-Feb-2006 01:42


Be carefull when your searching position is in first index. For example:



$newsbody = "<p>This is paragraph</p>";



if( strpos( $newsbody, "<p>" ) == 0 ) {

   // do something

}



when strpos returns FALSE, this "if block" will be executed by PHP, because FALSE also has 0 value. So, you have to make it a little bit longer of code:



$pos = strpos( $newsbody, "<p>" );

if ( $pos != FALSE ) {

    $pos = strpos( $newsbody, "<p>" );

    if( $pos == 0 )

        $newsbody = substr( $newsbody, 3 );

}

luko1 at centrum dot cz
02-Feb-2006 04:11


<?php  //prepocet velikosti souboru

function format($soubor) {

  $velikost = filesize($soubor);

  if($velikost < 1048576):

    return number_format(($velikost / 1024), 2, ',', ' ')." kB";

  else:

    return number_format(($velikost / 1024 / 1024), 2, ',', ' ')." MB";

  endif;

}

?>

<?php

function read_dir($dir)

{

  $path = opendir($dir);

  while (false !== ($file = readdir($path))):

    if ($file!="." && $file!=".."):

      if (is_file($dir."/".$file)):

        $items[] = $file;

      else:

        $items[] = $dir."/".$file;

      endif;

    endif;

  endwhile;

  closedir($path);

  if ($items):

    natcasesort($items);

    foreach ($items as $item){

      if (is_dir($item)):

        $dir1 = $item;

        $item1 = substr($item, strrpos($item, '/') + 1).'/';

        echo "<b>$item1</b><table border=1 style='margin-left: 60px; position: static; border: blue'><tr><td>";

        read_dir($dir1);

        echo "</table>";

      else:

        $cesta_file = "\"".$dir."/".$item."\"";

        $cesta_size = $dir."/".$item;

        echo "<span class=pop>&nbsp;<a href=$cesta_file title=$item>$item</a> <span> - ".format($cesta_size)."</span> </span><br>";

      endif;

    } //endforeach

  endif;

}

?>

...

<table><tr><td>

<?php

$dir = ".";

read_dir($dir);

?>

</table>

anonymous at example dot com
02-Feb-2006 07:58


Beware of following the examples too closely...



$str = "abcdef";

echo strpos($str, 'b'); // outputs 1



however



$str = "abc\nef";

echo strpos($str, '\n'); // output nothing (FALSE)



Not a great way to try to stop PHP email injection attacks (as I found out).



Instead use 

strpos($str, "\n")



because the escapes are processed only when using double quotes.

adispam at uid0 dot sk
09-Jan-2006 06:30


$a="nice string 1234 with number";

$b=sprintf("nice string %d", 1234);

var_dump(strpos($a,$b));



returns FALSE.

substitute : $b=sprintf("nice string %d", 1234);

with: $b = "nice string "; $b.=(string)1234;

and you 'll get correct result (0)

msandersen at t tpg dot com dot au
09-Jan-2006 06:15


<?PHP

$txt = preg_replace("|(<script.+</script>)|Usi", "", $txt);

?>

No point in keeping empty script tags. Ungreedy will prevent overzealous content removal where there are more than one set of script tags on the page. Multiline has no use here.

Otherwise, if you absolutely must have the empty tags:

<?PHP

$txt = preg_replace("|<script[^>]*>(.+)</script>|Usi", "", $txt);

?>



Martin

horst
04-Jan-2006 02:46


Why in such a way?

<?

$txt = preg_replace("/<script(.*)<\/script>/sim", "", $txt);

?>

samuraj at xmail dot cz
24-Dec-2005 01:38


there was a code (from wodzuY2k at interia dot pl) removing all between <script> tags..

but it didn't work if the tag begins like <SCRIPT language=javascript type=text/javascript> 



here is function removing all between "<script"  and  "/script>"



<?php



function remove_js($contents)            

{

  while(true) 

  { 

   $begPos = strpos($contents,"<script"); 

   if ($begPos===false) break; //all tags were found & replaced. 

   $endPos = strpos($contents,"/script>",$begPos+strlen("<script")); 

   $tmp = substr($contents,0,$begPos); 

   $tmp .= substr($contents,$endPos+strlen("script>")); 

   $contents = $tmp; 

   if ($loopcontrol++>100) break; //loop infinity control 

   continue;  //search again 

  } 

  return $contents;



}



?>

Virtual Hunter root(at)autocrash(dot)ru
23-Dec-2005 07:44


If you want to find positions of all needle's in haystack,

you can use this one:



while (($pos=strpos($haystack,$needle,$pos+1))!==false) $pos_array[$i++]=$pos;



But mind, that it will find from second char. You must use $pos=-1; before you want search from first char.



{ 

$haystack="one two three one two three one two three one two three one";

$needle="one";



$pos=-1;

while (($pos=strpos($haystack,$needle,$pos+1))!==false) $pos_array[$i++]=$pos;

}



RESULT:



$pos_array[0] = 0

$pos_array[1] = 14

$pos_array[2] = 28

$pos_array[3] = 42

$pos_array[4] = 56

rycardo74 at gmail dot com
22-Nov-2005 09:19


this function return all src properties from a html text

in array you can filter the specifics html tags with strip_tags



$HTML=strip_tags ( $HTML, '<img>' );

$tag = trip_tag_prop("src=\"" , "\"" , $HTML);



function trip_tag_prop($ini,$end,$HTML ){

$ini_len= strlen($ini);

$end_len= strlen($end);

$inizio_pos=0;

while($inizio_pos  = strpos ( $HTML, $ini, $inizio_pos)){

$fine_pos     = strpos ( $HTML, $end,($inizio_pos + $ini_len));

$tag[]        = substr ( $HTML, $inizio_pos + $ini_len ,($fine_pos - $inizio_pos - $ini_len) );

$inizio_pos=$fine_pos;

}

return $tag;

}



by :Auayama , cabrera  rycardo74 (a) gmail (dot) com

csaba at alum dot mit dot edu
21-Nov-2005 06:00


function nthPos ($str, $needles, $n=1) {

    //    finds the nth occurrence of any of $needles' characters in $str

    //  returns -1 if not found; $n<0 => count backwards from end

    //  e.g. $str = "c:\\winapps\\morph\\photos\\Party\\Phoebe.jpg";

    //       substr($str, nthPos($str, "/\\:", -2)) => \Party\Phoebe.jpg

    //       substr($str, nthPos($str, "/\\:", 4)) => \photos\Party\Phoebe.jpg

    $pos = -1;

    $size = strlen($str);

    if ($reverse=($n<0)) { $n=-$n; $str = strrev($str); }

    while ($n--) {

    $bestNewPos = $size;

    for ($i=strlen($needles)-1;$i>=0;$i--) {

        $newPos = strpos($str, $needles[$i], $pos+1);

        if ($newPos===false) $needles = substr($needles,0,$i) . substr($needles,$i+1);

        else $bestNewPos = min($bestNewPos,$newPos); }

    if (($pos=$bestNewPos)==$size) return -1; }

    return $reverse ? $size-1-$pos : $pos;

}



Csaba Gabor from Vienna

dale at ucsc dot edu
11-Nov-2005 02:28


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;

}

?>

johnjc-phpdocs at publicinfo dot net
01-Nov-2005 10:37


The === and !== are not fully documented in either the Comparison Operator, Booleans type sections. They are talked about a bit more in the sections on strpos() and array_search() but they refer you to the section on Booleans for further information. 



I am putting my contribution on === and !== in the Booleans section with pointers to it from the comment areas of other sections.



http://uk.php.net/manual/en/language.types.boolean.php

info at quantummechanic dot com
06-Oct-2005 05:42


this function takes a space-deliminted string as a list of potential needles and runs it against another string as a haystack.



the number of positive matches of needles within the haystack is returned as a rounded percentile.



function keyMatch($needles,$haystack) {

    $nArray=split(" ",$needles);

    $found=0;

    $best=count($nArray);

      for($i=0;$i<count($nArray);$i++) {

        $pzn=strpos(strtoupper($haystack),strtoupper($nArray[$i]));

        if ($pzn>-1) { $found++; }

       }

    $pct=($found*100)/$best;

    return round($pct);

}



$test = keyMatch("the quick wolf","the quick brown fox jumps over the lazy dog");

echo($test);



RESULT:



67



(because "the" and "quick" were found but "wolf" was not)

paul at goldenbakery dot nl
28-Sep-2005 01:51


@talthen at wp dot pl



Or you could just have typed:



if (strpos($string,$searchfor)===0)) ....



All you needed was en extra = instead of a whole function.

talthen at wp dot pl
31-Aug-2005 03:48


Because I like the way pascal functions work, so I created this little function:



function paspos($base,$findme)

{

$result=strpos($base,$findme);

if ($result===false) $result=-1;

return $result;

}



It returns -1 if the $findme may not be found in $base, or position where $findme was found in $base.



Now when you want to check if $base starts from $findme you can just type:

if (paspos($string,$searchfor)==0)) ....



Hope you'll like it :)

lindbeer at gmail dot com
26-Jul-2005 01:29


He he. I've got an updated version of the multiStrposArray function:



<?php



function multiStrposArray($haystack, $needle) {

    return explode($needle, $haystack);

}



?>

vig0
11-Jul-2005 06:03


This function takes in a string and a delimiter. It then builds an array of the data in between the delimiter then returns the array. I needed this function for something that I'm doing and thought it was somewhat useful.



function multiStrposArray($haystack, $needle){

  $array = array();

  $row   = 0;

  $var   = "";

  for ($i=0; $i<strlen($haystack); $i++) {

    if (substr($haystack, $i, 1)==$needle) {

      $array[$row] = $var;

      $row++;

      $var = "";

    } else {

      $var .= substr($haystack, $i, 1);

    }



  }

  if ($var) $array[$row] = $var;

  return $array;

}

Ed Lecky-Thompson
26-Apr-2005 09:02


Here's a quick function which can replace strtotime, and will work fine on dates pre-1970 (i.e. it will return a negative number as expected).



This negative time stamp seems to be supported as an input parameter by methods like date() up to a point, but if you get crazy and start talking about dates in the 1700s (everybody was using PHP3 back then, of course) it gets upset.



For those of you doing staff databases and so forth, of course, this is probably fine - it's definitely OK for any dates post 1900, and this value has been hard coded into the function below.



    function safestrtotime($strInput) {

        $iVal = -1;

        for ($i=1900; $i<=1969; $i++) {

            # Check for this year string in date

            $strYear = (string)$i;

            if (!(strpos($strInput, $strYear)===false)) {

                $replYear = $strYear;

                $yearSkew = 1970 - $i;

                $strInput = str_replace($strYear, "1970", $strInput);

            };

        };

        $iVal = strtotime($strInput);

        if ($yearSkew > 0) {

            $numSecs = (60 * 60 * 24 * 365 * $yearSkew);

            $iVal = $iVal - $numSecs;

            $numLeapYears = 0;        # Work out number of leap years in period

            for ($j=$replYear; $j<=1969; $j++) {

                $thisYear = $j;

                $isLeapYear = false;

                # Is div by 4?

                if (($thisYear % 4) == 0) {

                    $isLeapYear = true;

                };

                # Is div by 100?

                if (($thisYear % 100) == 0) {

                    $isLeapYear = false;

                };

                # Is div by 1000?

                if (($thisYear % 1000) == 0) {

                    $isLeapYear = true;

                };

                if ($isLeapYear == true) {

                    $numLeapYears++;

                };

            };

            $iVal = $iVal - (60 * 60 * 24 * $numLeapYears);

        };

        return($iVal);

    };

yess at eleethal dot com
24-Apr-2005 08:18


Regarding James Perlman's findStr(), it's very nice although doesnt always return true when it should.  I found fnmatch() to be a more accurate function for 'wildcard matching'. I'm building an IRCd and require wildmatching for many different commands. Hope this helps somone.



<?

findStr("12.12.12.*","12.12.12.12"); //returns null, should return true



fnmatch("12.12.12.*","12.12.12.12"); //returns 1.

?>

webKami [at] akdomains.com
01-Apr-2005 12:37


You can easily skip these two meaningless comment lines in my last function.These comments are for old version of the function, I was not using length of needle in that version. Code is fine itself, I suppose ;)

<?

...



//start $pos from -1, cause we are adding 1 into it while searchig

//so the very first iteration will be 0



...

?>

webKami [at] akdomains.com
31-Mar-2005 07:06


Str Pos Nth (Position of nth occurance of a string)

A handy function to get the position of nth occurance of a substring in a string, with an optional param to make it case insenstive. I am calling it strposnth, suggestions welcome.



Third optional parameter gets the value of n, e.g puting in 2 will return position of second occurance of needle in haystack: Valid inputs (1 = default) 2,3,4..... 



Fourth optional parameter can be used to specify the function as case insenstive: Valid inputs (0 = case senstive = default) 1 = case insenstive.



Code:

<?



function strposnth($haystack, $needle, $nth=1, $insenstive=0)

{

    //if its case insenstive, convert strings into lower case

    if ($insenstive) {

        $haystack=strtolower($haystack);

        $needle=strtolower($needle);

    }

    //count number of occurances

    $count=substr_count($haystack,$needle);

    

    //first check if the needle exists in the haystack, return false if it does not

    //also check if asked nth is within the count, return false if it doesnt

    if ($count<1 || $nth > $count) return false;



    

    //run a loop to nth number of accurance

    //start $pos from -1, cause we are adding 1 into it while searchig

    //so the very first iteration will be 0

    for($i=0,$pos=0,$len=0;$i<$nth;$i++)

    {    

        //get the position of needle in haystack

        //provide starting point 0 for first time ($pos=0, $len=0)

        //provide starting point as position + length of needle for next time

        $pos=strpos($haystack,$needle,$pos+$len);



        //check the length of needle to specify in strpos

        //do this only first time

        if ($i==0) $len=strlen($needle);

     }

    

    //return the number

    return $pos;

}



?>



I just construct this function after trying to search a similar one to use in a shopping cart. I am using this to display a limited number of lines or text for featured products. My aim is to limit the product description to 100 characters or 3 lines / 3 list items whichever is less.



Example code goes like this

<?



//get the product description from recordset

$text=$row['product_desc'];



//strip off text if its longer than 100 characters

if (strlen($text)>100) $text=substr($text,0,100)." ...";



//get ending of the third line

$pos=strposnth($text,"\n",3,1);



//if found, strip off text after that

if($pos) $text=substr($text,0,$pos);



//nl2li (new line 2 list) this function converts the \n seprated lines of text into sorted or unsorted lists

//I have posted this function in nl2br

//http://uk2.php.net/manual/en/function.nl2br.php

$text=nl2li($text); 

echo $text;



?>



Examples:



strposnth("I am trying to go now.","o"); // returns 13 (strpos behavior)

strposnth("I am trying to go now.","O"); // returns false (strpos behavior)

strposnth("I am trying to go now.","o",2); // returns 16 (second occurance)

strposnth("I am trying to go now.","o",7); // returns false (occurance count is less than 7)

strposnth("I am trying to go now.","O",1,1); // returns 13 (stripos behavior)

strposnth("I am trying to go now.","O",3,1); // returns 19 (stripos behavior + nth occurance)



Suggestions and corrections are welcome.

Regards,



webKami [at] akdomains.com

edykory at bluebottle dot com
23-Mar-2005 04:49


a shorter version of "admin at bwongar dot com" searching function:



function strpos_array($haystack, $needle){

  while (($pos = strpos($haystack, $needle, $pos)) !== FALSE)

                 $array[] = $pos++;

  return $array;

}

 I like "arias" version, but I guess strlen(aguja) can be cached in a local variable.

damy_belthazor86 at yahoo dot it
09-Mar-2005 12:10


Aw.. I forgot to post the usage of my function :)



Here's an example in which an array is filled of all the values of the attribute src of the tag img.

<?php

$imgSrcValues = getTagAttributeValues($rteHtml,"<IMG","src=");

?>



bye!

07-Mar-2005 04:32


<?



// You can use this to get the real path...



$include_path = getenv("PATH_TRANSLATED");



echo $include_path = substr($include_path, strpos($include_path, "/"), strrpos($include_path, "/"));



?>

arias at elleondeoro dot com
07-Feb-2005 06:33


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.



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;

}

admin at bwongar dot com
20-Jan-2005 06:17


I created a useful function that returns an array with the positions within a string. For more info, read the comments:

<?php

// Returns an array in this fashion:

// array(count => position)

function strpos_array($haystack, $needle){

   $kill    = 0;    // Kills while loop when changed

   $offset    = 0;    // Offset for strpos()

   $i        = 0;    // Counter, not iterator



   while ($kill === 0) {

       $i++;

       $result = strpos($haystack, $needle, $offset); 



       if ($result === FALSE) {        // If result is false (no more instances found), kill the while loop

           $kill = 1;

       } else {

           $array[$i] = $result;    // Set array

           $offset = $result + 1;    // Offset is set 1 character after previous occurence

       }



   }



   return $array;



}

?>

Benjamin
09-Jan-2005 10:46


James Perlman's function is nice but he should REALLY use a regular expression:



http://php.net/manual/en/function.ereg.php

takapz at flor dot it
03-Dec-2004 09:28


here a little function for tag parsing



function parsing($tag,$string) {

        $start=strpos($string,"<" . $tag . ">" );

        $start=$start + strlen("<" . $tag . ">");

         $end=(strpos($string, "</" . $tag . ">"));

         $num=  ($end - $start);

         $valore=substr($string,$start,$num);

          return $valore;

}

James Perlman
11-Nov-2004 12:06


Here's a nifty function i made, that allows you to search a string using wildcards.  It was intentionally made as part of a ban system.



Here is the function:

(below is how to use the function)



<?php

function findStr($search, $target) {

    $matches = 0;

    $search = strtolower($search);

    $target = strtolower($target);

    $output = "";

    // Create the "search" array, which holds all our search terms

    $search = explode("*",$search); // You could change this to: '$search = explode(" ",$search);' if you wanted your search terms to be split by a space.

    $pos = 0;

    for ($i=0; $i<count($search); $i++) {

        // Check if the current search term is in our target

        if (strpos($target, $search[$i], $pos) != '' && strlen($search[$i])>0) {

            $pos = strpos($target, $search[$i], $pos);

            $matches++;

        } 

        if (strlen($search[$i])<1) {

            $matches++;

        }

    }

    if ($matches == count($search)) {

        return true;

    } else {

        return false;

    }

}

?>



How to use the function:

<?

echo findStr("34.12.85.*","34.12.85.98"); // would return true

echo findStr("3*.12.*.90","39.16.29.34"); // would return false

?>

The function searches to see if all the search terms are in the string, and if they are in the exact order you gave them in.



Hope you found this function to be helpful!

-James

ygrange at science dt uva dt nl
13-Sep-2004 04:15


Hmm. I think the maker of multi_strpos forgot to add that it allowed a negative position (if $n=0, $position[($n-1)] = $position[-1]. I just changed a slightly bit of the code to make it really correct. 



I just replace 

$position[$n] = (strlen($fragment[0]) + $position[($n-1)]);

by

$position[$n] = (strlen($fragment[0]) + $positione[$n]);

$positione[$n+1]=$position[$n];

philip
25-Aug-2004 03:52


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 = 0) {


    if ($insensitive) {


        return (false !== stristr($haystack, $needle)) ? true : false;


    } else {


        return (false !== strpos($haystack, $needle))  ? true : false;


    }


}


?>

christian dot NEI_TIL_SPAM at datalogen dot no
19-Aug-2004 11:26


If you want to find the position of the first character succeeding $needle, this function does it for you. $offset is optional.



<?php



function strpos_succ($haystack, $needle) {

    $offset = (func_num_args() > 2) ? func_get_arg(2) : 0;

    $res = strpos($haystack, $needle, $offset);

    return (($res === false) ? false : $res + strlen($needle));

}



?>



Example:

<?php

    $str = 'Mighty <a href="nowhere.htm">useful</a> function, this strpos_succ!';

    //Where does the first <a> tag in $str end?

    $aPos = strpos_succ($str, ">");

    // $aPos=29

?>

php .at. wwwcrm .dot. com
19-Aug-2004 10:33


Watch out for type!



The following code will return "not matched", which is a little counter-intuitive.



<?php

$val1=123;

$val2="123,456,789";

if (strpos($val2, $val1)!==false) echo "matched";

else echo "not matched";

?>



When $val1 is cast to string, it behaves as you might expect:



<?php

$val1=(string)123;

$val2="123,456,789";

if (strpos($val2, $val1)!==false) echo "matched";

else echo "not matched";

?>



Hope this saves someone the couple of hours that it took me to spot it :-)



Regards,

Alex Poole

bishop
21-Apr-2004 03:38


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);

}

?>

amy_w at gmx dot de
02-Apr-2004 09:41


You can use this function to find ANY occurence of a string in an array - no matter if it is just part of one of the array elements.





it returns the key of the first found occurence or false





<?php


function search_array($needle,$haystacks) {


    $found=false;


    foreach ($haystacks as $key => $haystack) {


        if (!(strpos($haystack,$needle)===false)) {


            $found=$key;


            break;


        }


    }


    return ($found);


}


?>

ebypdx at comcast dot net
09-Mar-2004 05:26


counting the occurrences of a substring, recursive-style instead of looping.

<?

function countSubstrs($haystack, $needle)

{

    return (($p = strpos($haystack, $needle)) === false) ? 0 : (1 + countSubstrs(substr($haystack, $p+1), $needle));

}

?>

nanobot2k at nanobot2k dot org
15-Feb-2004 01:45


This function will return the number of times a needle is found in a haystack...if none that it will return 0.



Cheers to lgbr for saving me the headache! :P

<?php

/**

 * @return int

 * @param string $haystack

 * @param string $needle

 * @desc returns the number of times a needle is found in a haystack, 0 if none found

*/

function totalStr($haystack, $needle,$i = 0)

{

    while(strpos($haystack,$needle) !== false) {

        $haystack = substr($haystack, (strpos($haystack,$needle) + 1));

        $i++;

    }

    return $i;

}

?>

kingbusiness at hotmail dot com
18-Dec-2003 10:34


A simple function to find the number of occurances in a string within a string





<?php


function StringCount($searchstring, $findstring)


{


    return (strpos($searchstring, $findstring) === false ? 0 :  count(split($findstring, $searchstring)) - 1);


}


?>

jackylee at eml dot cc
19-Nov-2003 10:17


enough to search and replace a new string into a text file.


hope this can save your time :-)





original config.txt file:


Current Background = [wallpaper/WinXP.jpg]


Last Time = [20]





<?php


  $var = file_get_contents("data/config.txt");





  $out = fopen("data/config.txt", "w");


  $var2 = writeConfig($var , "Current Background = [" , "]" , "wallpaper/Bgred.jpg");  


  $var2 = writeConfig($var2, "Last Time = [" , "]" , "21");  


  fwrite($out, $var2);


  fclose($out);  





function writeConfig($var, $begString, $endString, $newString) 


{


  $begPos = strpos($var,$begString) +strlen($begString);


  $endPos = strpos($var , $endString , $begPos);


  $result = substr($var, 0, $begPos);


  $result .= $newString;


  $result .= substr($var, $endPos);


  return $result;


}


?>





changed config.txt file:


Current Background = [wallpaper/Bgred.jpg]


Last Time = [21]

peous at djingle dot com
03-Oct-2003 01:54


Function to find the first occurence of any object of the array.





<?php


function findfirstof( $txt, $arr, $start )


{


    $pos = -1;


    foreach( $arr as $v )


    {


        $p = strpos( $txt, $v, $start );


        if ($p===FALSE)


            continue;


        if (($p<$pos)||($pos==-1))


            $pos = $p;


    }


    return $pos;


}


?>





Ex:


$str = "find, the first word...";


$firstW = findfirstof( $str, ",?.:!" ); //returns "find"

justin at visunet dot ie
01-Oct-2003 09:20


Function:


stripos_words($haystack,'words in string')





This function finds and reports positions of all words in supplied haystack. It returns the results as an array. The array has the following structure.





Array


(


    [69] => Array


        (


            [start] => 69


            [end] => 74


            [word] => honey


        )





    [226] => Array


        (


            [start] => 226


            [end] => 232


            [word] => cobweb


        )


}





Where, for convenience, the main key also contains the positions of each found word occurrence.





If you want the main key to be 0,1,2,3,etc then set the third parameter ($pos_as_key) to false;





Hope this is of help to someone.





Cheers,


Justin :)





<?php


function stripos_words($haystack,$needles='',$pos_as_key=true)


{


    $idx=0; // Used if pos_as_key is false


    


    // Convert full text to lower case to make this case insensitive


    $haystack = strtolower($haystack);


    


    // Split keywords and lowercase them


    foreach ( preg_split('/[^\w]/',strtolower($needles)) as $needle )


    {


        // Get all occurences of this keyword


        $i=0; $pos_cur=0; $pos_found=0;


        while (  $pos_found !== false && $needles !== '')


        {


            // Get the strpos of this keyword (if thereis one)


            $pos_found = strpos(substr($haystack,$pos_cur),$needle);


            if ( $pos_found !== false )


            {


                // Set up key for main array


                $index = $pos_as_key ? $pos_found+$pos_cur : $idx++;


                


                // Populate main array with this keywords positional data


                $positions[$index]['start'] = $pos_found+$pos_cur;


                $pos_cur += ($pos_found+strlen($needle));


                $positions[$index]['end']   = $pos_cur;


                $positions[$index]['word'] = $needle;


                $i++;


            }


        }


    }





    // If we found anything then sort the array and return it


    if ( isset($positions) )


    {


        ksort($positions);


        return $positions;


    }





    // If nothign was found then return false


    return false;


}


?>

daijoubu at videotron dot ca
30-Aug-2003 04:48


To previous comments:

I did a test with 500000 iterations, string lenght was 1846bytes long and the word to find was near the end.



Results:

if (*)

Total time in secs

Average



strpos($test, 'Possibly') === true

5.1114

0.0000102228 



strpos(' '.$test, 'Possibly') > 1

7.2559

0.0000145117 



is_int(strpos($test, 'Possibly'))

5.5331

0.0000110661 



strstr($test, 'Possibly')

5.1461

0.0000102922



Clearly shows that === operator is the fastest

wodzuY2k at interia dot pl
07-Apr-2003 03:31


this loop removes <script>.*</script> tags from HTML contents. 





<?php


while(true)


{


    $begPos = strpos($contents,"<script");


    if ($begPos===false) break; //all tags were found & replaced.


    $endPos = strpos($contents,"script>",$begPos+strlen("<script"));


    $tmp = substr($contents,0,$begPos);


    $tmp .= substr($contents,$endPos+strlen("script>"));


    $contents = $tmp;


    if ($loopcontrol++>100) break; //loop infinity control


    continue;  //search again


};


?>

bebop at gmx dot at
31-Mar-2003 06:02


just another workaround for the true/0 problem:





<?php


if (!is_int(strpos($haystack,$needle))) {


    //do something


}


?>





should also do the job

arduenn at hotpop dot com
17-Jan-2003 04:45


Hi all,



This function returns an array of positions (as integers) of a regular expression pattern that could occur several times within a string (or FALSE if the pattern does not occur). Note that the function is able to determine the positions of overlapping patterns. There may be shorter ways of determining multiple pattern positions (such as by using 'explode') but likely these won't find the overlapping patterns.



The multi_strpos function has one restriction (for the sake of snippet economy): if you use a pattern starting with '\*' (backslash asterisk) a hit within the string will invoke an infinite loop.



This function was initially written to create restriction maps of DNA sequences but you may find other uses.



<?



function multi_strpos($pattern, $sequence) {

  $n = -1;

  while (ereg($pattern, $sequence)) {

    $n++;

    $fragment = split($pattern, $sequence);

    $trimsize = (strlen($fragment[0]))+1;

    $sequence = "*".substr($sequence, $trimsize);

    $position[$n] = (strlen($fragment[0]) + $position[($n-1)]);}

  return $position;}



// Below some code to demonstrate the function.



$testsequence = "She sells sea shells at the see shore.";

echo "Test sequence = '$testsequence'\n\n";



$testpattern = "s...s";

echo "Regular expression pattern = '$testpattern'\n\n";



$position = multi_strpos($testpattern, $testsequence);



if ($position) {

  echo "Pattern match found at:\n";

  while (list($index, $pos) = each($position)) {

    echo "$pos\n";}}



?>

netmail at brownfloyd dot com
29-Dec-2002 10:31


Description:





array straipos ( string haystack, array needle [, int offset])





Returns an indexed array of the item from the array 'needle' that occurs first in the haystack, with item 0 being its position in the 'haystack', and item 1 being the item number of the item found.





If none of the items are found, it returns false.





<?php


function straipos($haystack,$array,$offset=0)


{


    $occ = Array();


    for ($i = 0;$i<sizeof($array);$i++)


    {


        $pos = strpos($haystack,$array[$i],$offset);


        if (is_bool($pos)) continue;


        $occ[$pos] = $i;


    }


    if (sizeof($occ)<1) return false;


    ksort($occ);


    reset($occ);


    list($key,$value) = each($occ);


    return array($key,$value);


}


?>

admin at kingdompeople dot com
26-Sep-2002 01:19


the following 2 functions grab a piece of content from an external html and lists that in separate places -- i.e. the title for html documents, or a list of subtopics dynamically.. the first function grabs the first found and returns a string, the second recursively searches the rest of the document and returns an array.. 


I found this was very useful to display articles on my website that had various topics marked by a consistent <P class=subtopic>, and the end </ P> tags.. 





<?php


function stripfromtext($haystack, $bfstarttext, $endsection) {


  $startpostext = $bfstarttext;


  $startposlen = strlen($startpostext);


  $startpos = strpos($haystack, $startpostext);


  $endpostext = $endsection;


  $endposlen = strlen($endpostext);


  $endpos = strpos($haystack, $endpostext, $startpos);


  return substr($haystack, $startpos + $startposlen, $endpos - ($startpos + $startposlen));


}





function &stripfromtextarray($haystack, $bfstarttext, $endsection, $myarray=array(), $offset=0) {


  $startpostext = $bfstarttext;


  $startposlen = strlen($startpostext);


  $startpos = strpos($haystack, $startpostext, $offset);


  $endpostext = $endsection;


  $endposlen = strlen($endpostext);


  $endpos = strpos($haystack, $endpostext, $startpos);


  $myarray[] = substr($haystack, $startpos + $startposlen, $endpos - ($startpos + $startposlen));


  $offset = $endpos;


  if (is_numeric(strpos($haystack, $startpostext, $offset))) {


    return stripfromtextarray($haystack,$startpostext, $endpostext, &$myarray, $offset);


  }


  else {


    return $myarray;


  }


}


?>





The following is an example of the use of these functions


<?php


$filetitle = stripfromtext ($content, "<P CLASS=title>", "</ P>");





// and


$rightmenuarray = stripfromtextarray($content, "<P CLASS=subtitle>", "</ P>");





foreach ($rightmenuarray as $rm) {$rightmenu.=$rm."<br>";}


?>

anonymous dot coward at slashdot dot org
20-Sep-2002 02:19


Even simpler method to get around that zero/false headache:



if (strpos(' '.$string,$substring) > 1)

{

  echo('substring present!');

}



Simly add a space to your string being tested. Your first real string position then becomes 1, and zero really means "string not found". Please adjust your position formulas accordingly (substract 1).

http://cm.zetyx.net/
18-Sep-2002 12:48


About issue:

Zero (0) is not a false result; it is a valid answer. The function returns 0 because "abc" does indeed contain "abc" and the first occurence of the target string starts at position 0.

Use === to test if the function returned true or false.



Try my simple and easy way for use at several PHP version.



$buf = "When doves cry.";

$chk = "Wh";

if (strpos( "#$%".$buf, $chk)) { return TRUE; }

else { return FALSE; }

one at groobo dot com
15-Aug-2002 01:04


You all know it probably, but it is quicker to use strpos() function to check an existence of a character in a string, instead of regular expressions.

dont at spam dot net
24-Jul-2002 07:14


To: redeagle@chello.nl



Zero (0) is not a false result; it is a valid answer. The function returns 0 because "abc" does indeed contain "abc" and the first occurence of the target string starts at position 0.

Use === to test if the function returned true or false.

redeagle at chello dot nl
23-Jul-2002 08:39


I've just did a test using strpos:

-

$test = strpos("abc", "abc");

echo($test);

-

Note that $test will return zero (false) if the seccond parameter is the same as the first parameter.

schofiel at cs dot ualberta dot ca
19-Jul-2002 12:46


Only 0 is false in PHP non-zero is postive

so -2 could be a true.



Since they can't use zero becuase it is in

the range of possible correct positions within

a string.



So do the type check against false explicity

to prevent odd behavior

jjrocket at yahoo dot com
04-May-2002 01:22


It may be obvious to most, but the number returned by strpos will be the position in haystack at which the string needle starts. 



For example if haystack is "Now is the time" and needle is "Now", then strpos will return 0, not 2.

martin at netimage dot dk
19-Apr-2002 07:54


I use this



$a=strpos($haystack,$needle,$offset);



if($a!==false)  # note the check for type equivalence

// found

else

// not found

soletan at toxa dot de
09-Feb-2002 05:28


Better to use the original example from reference part for checking, if strpos failed or not with version before 4.03b.



When pos is an integer and is interpreted as boolean false (so it is 0) strpos FOUND something immediately at the haystack's beginning ...

maharj at DONTSPAMutu dot fi
14-Jan-2002 03:51


I'm not sure if this is common, but I'll take an example:



$str="123456test7890";



If I do:

for($i=0;$i<strpos($str, "te");$i++)

  print $str[$i];

print "Hey mon";

for($i=strpos($str,"st")+2;$i<strlen($str);$i++)

  print $str[$i];



on the second loop the strpos() returns something, that is not true. (pos=2 or something).



Solution: Before for:s take the boundaries to variables like:

$startPos=strpos($str, "te");

$endPos=strpos($str, "st")+2;

anduse them in for-loops



Yes, I know I can ereg("(.*)test(.*)",$str,$parm) but I just came across this...



The PHP version I'm using is 4.0.4pl1



:)Mikko

nmmm at nmmm dot nu
08-Jan-2002 05:44


if you want to check if a string includes some character, you may use code like this ('x' is in position 0 in the string so if $c is 'x' if structure will return false :)



$c='5';

$s='01234567890';

if (strpos($s, 'x'.$c))

    echo "$c is a number!";

Michael-Rudel at gmx dot de
22-Nov-2001 06:01


The example above for versions older than 4.0b3 should check for integer, since strpos returns an integer, not a string. So it should read:





// in versions older than 4.0b3:


$pos = strpos($mystring, "b");


if (is_integer($pos) && !$pos) {


    // not found...


}

GrandLibrarian at iname dot com
27-Apr-2000 09:02


To find the position of a string in a case-insensitive manner without converting everything to lowercase, try using stristr:<br>


$temp = stristr($haystack,$needle);<br>


$pos = strlen($haystack)-strlen($temp);

strpos

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