Question

In an application which is intended for germany ,am writing some webservices i have to apply some validation rules for username ,password etc.. like alphanumeric,special charecters not supported etc.. i have used regular expression to achive this but it fails,it works fine for english language,but it does not support German language, how can i tackle this issue.

Any help will be appreciated…preg_match("#.*^(?=.{8,20})(?=.*[a-zA-Z])(?=.*[0-9]).*$#", $string)

Answer 1

First, use the ‘u’ modifier for UTF-8 (whose encoding you should be using for international applications). Secondly, if you are trying to allow umlauts, etc. within the [a-zA-Z] block, you can add the specific characters you want using escape sequences as follows:

individually:

preg_match( "/\x{00FC}/u" , 'ü' ); // 1

or in a group:

preg_match('/^[\x{00DF}\x{00E4}\x{00C4}\x{00F6}\x{00D6}\x{00FC}\x{00DC}]+$/u', 'ßäÄöÖüÜ'); // 1

…or just use the word letter match \w (noting that this will also allow numbers and underscore and other international characters which can serve as word letters).

preg_match( "/\w/u" , 'ü' ); // 1

(I’m not sure what you are doing with the ^ in the middle of the expression, btw, without an ‘m’ modifier.)