Regex to disallow all Special Chars but allow German Umlauts in jQuery?

Question

I would like to allow all Alphanumeric Characters and disallow all Special Characters in a RegEx. But I would like to allow German Umlauts but becouse they are Special Chars too, I can't type them in. I use this Script:

    if(website_media_description.match(/[^a-zA-Z0-9]/g)) { 

    alert('Found Special Char');        

}

So when a äöüÄÖÜß is in the variable than I get the alert too. I also tryed this Script:

    if(website_media_description.match(/[^a-zA-Z0-9äöüÄÖÜß]/g)) { 

    alert('Found Special Char');        

}

But this also does not work. Can someone please tell me what I am doing wrong?

Thanks :)

Answer 1

my test String comes from an input field, i write "description test 1 öäüÖÄÜß"

Your problem is coming from the fact you haven't considered every character you want in your whitelist.

Let's consider what is actually matched by your test string

"description test 1 öäüÖÄÜß".match(/[^a-zA-Z0-9äöüÄÖÜß]/g);
// [" ", " ", " "]

As we can see, it matched 3 times, and each time was whitespace. So, the solution is to add a space to your whitelist (assuming you don't want to allow tab/return etc).

"description test 1 öäüÖÄÜß".match(/[^a-zA-Z0-9äöüÄÖÜß ]/g);
// null

Your test string now passes the RegExp without a match, which means it is valid in this case.

Answer 2

For some reason I needed to use the unicode representation:

[^a-zA-Z0-9\u00E4\u00F6\u00FC\u00C4\u00D6\u00DC\u00df]`

Thanks to everyone :)