Как найти подстроку без учета регистра

<?php
function multineedle_stripos($haystack, $needles, $offset=0) {
    foreach($needles as $needle) {
        $found[$needle] = stripos($haystack, $needle, $offset);
    }
    return $found;
}// It works as such:
$haystack = "The quick brown fox jumps over the lazy dog.";
$needle = array("fox", "dog", ".", "duck")
var_dump(multineedle_stripos($haystack, $needle));
/* Output:
   array(3) {
     ["fox"]=>
     int(16)
     ["dog"]=>
     int(40)
     ["."]=>
     int(43)
     ["duck"]=>
     bool(false)
   }
*/
?>

strpos("123", 2) !== strpos("123", "2")

It is very bad practice to use the same function name as an existing php function but have a different output format.  Someone maintaining the code in the future is likely to be very confused by this.  It will also be hard to eradicate from a codebase because the naming is identical so each use of stripos() would have to be analyzed to see how it is expecting the output format (bool or number/bool).

Calling it string_found() or something like that would make a lot more sense for long-term use.

<?php function containsDescenders($text) {
    $descenders = array("g","j","p","q","y");
    foreach ($descenders as $letter) {
        if (stripos($text,$letter) !== false) {
            return true;
        }
    }
    return false;
} ?>

<?php
namespace My;//You can be free using core functions in your NameSpaces (My)
function stripos($haystack, $needle) {
    //To call core function (from global NS) you should add backslash only - func
    return (FALSE === stripos($haystack, $needle)) ? FALSE : TRUE;
}var_dump(stripos($haystack = 'John knows English language.', $needle = 'john')); //TRUE
var_dump(stripos($haystack = 'Sara knows English language too.', $needle = 'john')); //FALSE
?>

<?php

/****************************************

*    SAFE HIGHLIGHT

****************************************/

/**

* function finds and encase every string in a $needleArr array with

* strings $shearLft (from the left side) and $shearRgt (guess from which

* side).

* already encased needles are IGNORED for any other step, so order

* of needles in $needleArr is pretty important.

*

* function is searching needles in case-insensitive mode,

* but case in the subject is saved.

*

* can you do it better? so, do it.

*

* @param array $needleArr array of needles

* @param string $shearLft left shear

* @param string $shearRgt right shear

* @param string $subject subject

* @param string $encoding encoding ('utf-8' is default)

*

* @author griffin

*/

function safeHighlight( $needleArr, $shearLft, $shearRgt, $subject, $encoding = 'utf-8')

{
// encoding

    $e = $encoding;
// oh, no needles

    if( !is_array( $needleArr))

        return $subject;
// empty keys throw-off, only unique, reindex

    $nA = array_values(

            array_unique(

                array_diff( $needleArr, array(''))

            )

        );
// needle count

    if( !($nC = count( $nA)))

        return $subject; // nothing to hl

       
    // shear length

if( !(($rLL = mb_strlen( $rL = $shearLft, $e))

    + ($rRL = mb_strlen( $rR = $shearRgt, $e))))

        return $subject; // no shears

   
    // subject length

if( !($sL = mb_strlen( $s = $subject, $e)))

        return null; // empty subject

       
    // subject in lowercase (we need to aviod

    // using mb_stripos due to PHP version)

$sW = mb_strtolower( $s, $e);
// masking ~ 0=not changed, 1=changed

    $m = str_repeat( '0', $sL);
// loop for each needle

    for( $n=0; $n<$nC; $n++)

    {
// needle string loWercase

        $nW = mb_strtolower( $nA[ $n], $e);
$o = 0; // offset

        $nL = mb_strlen( $nW, $e); // needle length

        // search needle

while( false !== ($p = mb_strpos( $sW, $nW, $o, $e)))

        {

            // oh hurrey, needle found on $p position

           
            // is founded needle already modified? (in full-length)

for( $q=$p; $q<($p+$nL); $q++)

                if( $m[ $q])

                {

                    // ai, caramba. already modified, jump over

                    $o+= $nL;
// continue for while() loop - not for for() loop!

                    continue 2;

                }
// explode subject and mask into three parts

            // partA|needle|partB

            $sE[0] = mb_substr( $s, 0, $p, $e);

            $sE[1] = mb_substr( $s, $p, $nL, $e);

            $sE[2] = mb_substr( $s, $p+$nL, $sL-$p-$nL, $e);
// mask

            // partA|partB (needle not needed)

            $mE[0] = mb_substr( $m, 0, $p, $e);

            $mE[1] = mb_substr( $m, $p+$nL, $sL-$p-$nL, $e);
// apply shears

            $sE[1] = $rL.$sE[1].$rR;
// update sunject length

            $sL+= $rLL + $rRL;
// update mask

            $m = $mE[0] . str_repeat( '1', $rLL + $nL + $rRL) . $mE[1];
// implode into a subject

            $s = implode( $sE);
// update lowercase subject

            $sW = mb_strtolower( $s, $e);
// increase offset

            $o+= $rLL + $nL + $rRL;
// end of string reached

            if( $o>=$sL)

                break;

           
        }

// while()
} // for( $n=0; $n<$nC; $n++)

   
    // oouu yeaaa, kick the subject out of the function

return $s;

   
}

// function safeHighlight()

/****************************************

*    END: SAFE HIGHLIGHT

****************************************/

?>