Regex Match special characters between two characters

Question

So I have the following requirements:

1. Any alphabets between az or AZ
2. The first character must be alphabet
3. No numeric characters are allowed
4. No special characters are allowed except these three: .-'
5. And they can only be in between letters

So far, to solve this I have got the 2 following regex:

^[a-zA-Z][a-zA-Z ]*$

This is to solve points 1,2,3

(?<=[a-zA-Z])[.\-'](?=[a-zA-Z])

and this is to solve points 4,5

Test cases can be words like:

• abc (pass)
• abc's (pass)
• abc' (fail)
• abc ' (fail)

However I am unable to combine them. I have tried and I do not get the expected outcome. Any ideas?

Answer 1

You may use

^[a-zA-Z]+(?:[-.'][a-zA-Z]+)*$

See the regex demo

Details

• ^ - start of string
• [a-zA-Z]+ - 1+ ASCII letters
• (?:[-.'][a-zA-Z]+)* - 0 or more occurrences of
  • [-.'] - a hyphen, dot or single quote
  • [a-zA-Z]+ - 1+ ASCII letters
• $ - end of string