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I have problems with special characters =(

More information: http://www.question2answer.org/qa/48654
Q2A version: 1.7

1 Answer

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Create a filter plugin, see http://www.question2answer.org/qa/27723/dont-allow-people-to-register-with-some-usernames-like-admin

For your specific case you probably want a regex like

/[^A-Za-z0-9]/

If you match that, it means there is a non-alphanumeric character in there.
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Please add this function in core 1.8. Use for login name /[^A-Za-z0-9]/
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