Question

I am using this code but it doesn’t work correctly for – (mains) symbol

^\b\w{1,}(_\.-)?\w\b$ or ^\b\w{1,}(_\.\-)?\w\b$

The code above doesn’t work if string is like this: name-name

What I want to do with this code is:
Name most begin with Alphanumeric and aslo end, it can have this symbols (.-_) but only in the middle

name => true
Name_ => false
Name_sa => true
name._ => false  
name.-as => false

Answer 1

I think this should do it:

^[^\W_]+([_.-][^\W_]+)?$

Here the [^\W_] matches only any character except non-word characters and the _, so basically any word character except _. This is necessary as \w does contain _.