Regular Expression Sanitize (PHP)

问题

I would like to sanitize a string in to a URL so this is what I basically need.

Everything must be removed except alphanumeric characters and spaces and dashed.
Spaces should be converter into dashes.

Eg.

This, is the URL!

must return

this-is-the-url

回答1:

function slug($z){
    $z = strtolower($z);
    $z = preg_replace('/[^a-z0-9 -]+/', '', $z);
    $z = str_replace(' ', '-', $z);
    return trim($z, '-');
}

回答2:

First strip unwanted characters

$new_string = preg_replace("/[^a-zA-Z0-9\s]/", "", $string);

Then changes spaces for unserscores

$url = preg_replace('/\s/', '-', $new_string);

Finally encode it ready for use

$new_url = urlencode($url);

回答3:

This will do it in a Unix shell (I just tried it on my MacOS):

$ tr -cs A-Za-z '-' < infile.txt > outfile.txt

I got the idea from a blog post on More Shell, Less Egg

回答4:

Try This

 function clean($string) {
       $string = str_replace(' ', '-', $string); // Replaces all spaces with hyphens.
       $string = preg_replace('/[^A-Za-z0-9\-]/', '', $string); // Removes special chars.

       return preg_replace('/-+/', '-', $string); // Replaces multiple hyphens with single one.
    }

Usage:

echo clean('a|"bc!@£de^&$f g');

Will output: abcdef-g

source : https://stackoverflow.com/a/14114419/2439715

回答5:

All previous asnwers deal with url, but in case some one will need to sanitize string for login (e.g.) and keep it as text, here is you go:

function sanitizeText($str) {
    $withSpecCharacters = htmlspecialchars($str);
    $splitted_str = str_split($str);
    $result = '';
    foreach ($splitted_str as $letter){
        if (strpos($withSpecCharacters, $letter) !== false) {
            $result .= $letter;
        }
    }
    return $result;
}

echo sanitizeText('ОРРииыфвсси ajvnsakjvnHB "&nvsp;\n" <script>alert()</script>');
//ОРРииыфвсси ajvnsakjvnHB &nvsp;\n scriptalert()/script
//No injections possible, all info at max keeped

回答6:

The following will replace spaces with dashes.

$str = str_replace(' ', '-', $str);

Then the following statement will remove everything except alphanumeric characters and dashed. (didn't have spaces because in previous step we had replaced them with dashes.

// Char representation     0 -  9   A-   Z   a-   z  -    
$str = preg_replace('/[^\x30-\x39\x41-\x5A\x61-\x7A\x2D]/', '', $str);

Which is equivalent to

$str = preg_replace('/[^0-9A-Za-z-]+/', '', $str);

FYI: To remove all special characters from a string use

$str = preg_replace('/[^\x20-\x7E]/', '', $str);

\x20 is hexadecimal for space that is start of Acsii charecter and \x7E is tilde. As accordingly to wikipedia https://en.wikipedia.org/wiki/ASCII

Printable characters Codes 20hex to 7Ehex, known as the printable characters, represent letters, digits, punctuation marks, and a few miscellaneous symbols. There are 95 printable characters in total.

来源：https://stackoverflow.com/questions/3022185/regular-expression-sanitize-php

标签

php

regex

preg-replace

sanitization