Question

How to detect space, underscore is invalid? It has to be one word. But not working with

[^\w \xC0-\xFF]

• if i do \w\xC0-\xFF i can detect the space
• but how do i detect the ‘underscore’ ?

Inputs are invalid: username1234 _1234 or username 1234

Answer 1

Removing the space is easy as you already pointed out:

[^\w\xC0-\xFF]

Removing the underscore requires knowing that \w is the same as [0-9A-Za-z_]. So to also remove the underscore you can use this:

[^0-9A-Za-z\xC0-\xFF]