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Hi,
I'm using CE 6.6.1 using our own servers.
I'm trying to get a surname field to only allow text and one hyphen, no numbers or other chars.
I've added a regex to the regex field for the surname. The field highlights when invalid chars are entered but doesn't remove them.
Regex = /^[a-zA-Z]+(-[a-zA-Z]+)?$/

Does this need some javascript attaching to the survey to achieve this?

Thanks,
 

Regex only checks if there is something wrong and highlights it. It can't correct or remove anything.

If you want to remove things, you will have to find a Javascript solution (make sure your installation is setup so you can use Javascript).