Web студия "GrandView"

Описание

string strstr ( string haystack, string needle )

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

Если подстрока needle не найдена, возвращает FALSE.

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

Замечание: Эта функция учитывает регистр символов. Для поиска без учета регистра используйте stristr().

Пример 1. Пример использования strstr()

<?php $email = 'user@example.com'; $domain = strstr($email, '@'); echo $domain; // выводит @example.com ?>

Замечание: Если нужно лишь определить, встречается ли подстрока needle в haystack, используйте функцию strpos(), которая работает быстрее и потребляет меньше памяти.

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

См. также описание функций ereg(), preg_match(), stristr(), strpos(), strrchr() и substr().

add a note User Contributed Notes
strstr

fire.minded.design at gmail dot com
24-Sep-2007 04:06


for eamon:



preg_replace is wonderful for that sort of thing, amongst so much else.



<?php



$string = "a string with!0o|u7t stuf34-f2~ in#4 in it";



// No numbers

$string = preg_replace("![0-9]!", "", $string);

// $string is now "a string with!o|ut stuf-f~ in# in it"



// Nothing but alphabetic

$string = preg_replace("![^0-9A-Za-z\s]!", "", $string);

// $string is now "a string without stuff in in it"



?>

Christian Dywan
29-Jun-2007 07:25


@Eric:



Please do not test for the occurence of  a substring with strstr. As you should already have read above, strpos is much faster for this.

Eric
15-Jun-2007 05:26


Example 1. stristr() example

<?php

  $email = 'USER@EXAMPLE.com';

  echo stristr($email, 'e');

// outputs ER@EXAMPLE.com

?>



Example 2. Testing if a string is found or not

<?php

  $string = 'Hello World!';

  if(stristr($string, 'earth') === FALSE) {

    echo '"earth" not found in string';

  }

// outputs: "earth" not found in string

?>



Example 3. Using a non "string" needle

<?php

  $string = 'APPLE';

  echo stristr($string, 97); // 97 = lowercase a

// outputs: APPLE

?> 

I use this a lot at http://www.linksback.org

gigaman2003 at halfempty dot co dot uk
24-Feb-2007 12:48


Often you will need to find all occurrences of a string (for security escapes and such)



So I wrote this function to return an array with the locations of all the occurrences. Almost like an advanced strstr.



function findall($needle, $haystack)

{

    //Setting up

    $buffer=''; //We will use a 'frameshift' buffer for this search

    $pos=0; //Pointer

    $end = strlen($haystack); //The end of the string

    $getchar=''; //The next character in the string

    $needlelen=strlen($needle); //The length of the needle to find (speeds up searching)

    $found = array(); //The array we will store results in

    

    while($pos<$end)//Scan file

    {

        $getchar = substr($haystack,$pos,1); //Grab next character from pointer

        if($getchar!="\n" || buffer<$needlelen) //If we fetched a line break, or the buffer is still smaller than the needle, ignore and grab next character

        {

            $buffer = $buffer . $getchar; //Build frameshift buffer

            if(strlen($buffer)>$needlelen) //If the buffer is longer than the needle

            {

                $buffer = substr($buffer,-$needlelen);//Truncunate backwards to needle length (backwards so that the frame 'moves')

            }

            if($buffer==$needle) //If the buffer matches the needle

            {

                $found[]=$pos-$needlelen+1; //Add the location of the needle to the array. Adding one fixes the offset.

            }

        }

        $pos++; //Increment the pointer

    }

    if(array_key_exists(0,$found)) //Check for an empty array

    {

        return $found; //Return the array of located positions

    }

    else

    {

        return false; //Or if no instances were found return false

    }

}



Haven't had the chance to speed test it, but many optimizations should be possible. It just works enough for me. Hope it saves someone a lot of time.

eamon at gizzle dot co dot uk
29-Jan-2007 01:21


After some interesting projects that required the use of requiring only the chars of any given string i thought i'll just put it up. Simple code.



<?php

function strchrs($str)

{

    $n = strlen($str);

    $w = "";

    for($i = 0; $i < $n; $i ++)

    {

        if(!is_numeric($str[$i]))

        $w .= $str[$i];

    }

    return $w;

}

?>



Hey I'm building a new DB & Datasource abstraction layer, the framework's been built does anyone wannt help out. I need someone with a SYBASE database, and I'm also working on some new ways of dealing with XML contact me as I don't have much time to complete it. It's actually 3x faster than MDB2, and because it doesn't require PEAR its easier to install. Only OOP developers plz.

always_sleepz0r at removethisyahoo dot co dot uk
14-Jan-2006 11:38


//this is my little version



function rdir($d_d, $filter = null) {    

    $d = dir($d_d);while(false !== ($entry = $d->read())) {

     if ($entry!=".." && $entry!="." && $filter==null || true==stristr($entry, $filter)){ if (!is_dir($entry)) {

     $ret_arr['f'][]=$entry;}else{$ret_arr['d'][]=$entry;

    }}}$d->close();return $ret_arr;}



//usage:

$d="folder";



$dd=rdir($d);

//will return array with all files and folder names



$dd=rdir($d, "requiredneedle");

//will return array with only file/folder names containing "requiredneedle".



//$dd['f'] = files and $dd['d'] = folders

echo "<pre>";print_r($dd);echo "</pre>";

nospam AT thenerdshow.com
15-Nov-2005 04:20


It is a good practice to ensure dropdown menu submissions contain ONLY expected values:



$i=(isset($_POST['D1']))?$_POST['D1']:$o="Monday";

if (!stristr('Monday Tuesday Wednesday Thursday Friday Saturday Sunday',$i)) die();

(do database query)



This should protect against all known and unknown attacks, injection, etc.



User submitted should be cleaned through other functions.  See info under mysql_query

06-Jun-2005 09:13


suggestion for [leo dot nard at free dot fr]:

to be able to cut the string without having the html entities being cut in half, use this instead:



<?php



$oldstr = "F&ouml;r att klippa av en str&auml;ng som inneh&aring;ller skandinaviska (eller Franska, f&ouml;r den delen) tecken, kan man g&ouml;ra s&aring;h&auml;r...";



$length = 50;



# First, first we want to decode the entities (to get them as usual chars), then cut the string at for example 50 chars, and then encoding the result of that again.



# Or, as I had it done, in one line:

$newstr = htmlentities(substr(html_entity_decode($oldstr), 0, $length));

$newstr2 = substr($oldstr, 0, $length);

# It's not quite as much code as the snippet you've coded to remove the half-portions... ;)

# Hopefully somebody finds this useful!

echo "Without the decode-encode snippet:

$newstr2



With the decode-encode snippet:

$newstr";

?>



The above outputs this:



Without the decode-encode snippet:

F&ouml;r att klippa av en str&auml;ng som inneh&ar



With the decode-encode snippet:

F&ouml;r att klippa av en str&auml;ng som inneh&aring;ller skandin



First post in this db ;) 

Best regards, Mikael R