A string helper that replaces in-quote characters with a neutral one. It's good for handling things like SQL commands where quoted parts can contain keywords but you're not interested in them. Very simple tool, use with care.

deleteQuotedParts.php

<?php

function deleteQuotedParts($s,$replaceWith="#") {

    $inQuote = "";
    $protect = 0;
    $sl = strlen($s);
    $quoteChars = ["'"=>1,'"'=>1,"`"=>1];
    for($i=0;$i<$sl;++$i) {
        if($protect) {
            if($inQuote) $s[$i] = $replaceWith;
            $protect=0;continue;
        }
        $ch = $s[$i] ?: " ";
        $qc = isset($quoteChars[$ch]);
        if(!$inQuote) {if($qc) $inQuote=$ch;continue;}
        if($ch==$inQuote) {$inQuote="";continue;}
        if($ch=="\\") $protect=1;
        $s[$i] = $replaceWith;
    }

    return $s;

}