Regex for the specific chars at least appear once

Question

I have a requirement that validates the user input.

• only input a-z,A-Z, ', '-' and blanks.
• a-z,A-Z should appear at least once.

In other words:

• 'test user' --> True
• 'test1user' --> False
• ' test user' -' --> True
• ' ' --> False
• ' ' - ' --> False

I tried one way like ^[(A-Za-z)? '-]+$, but not work.

Any other solutions?

Answer 1

You may use this regex with a lookahead condition to ensure there must be at least one letter in input:

^(?=.*[a-zA-Z])[A-Za-z '-]+$

RegEx Demo

(?=.*[a-zA-Z]) is a positive lookahead condition that asserts presence of at least one letter in input text.