Question

I’ve been working for many hours trying to do a “simple thing”: use a regex to validate a text field.

I need to make sure of:

1- Only use (a-z), (A-Z) and (0-9) values
2- Add a SINGLE wildcard only at the end.

Ex.

Match

MICHE*

Match

JAMES

No match

MICHE**

No match

MIC_HEAL*

I have this regex till now:

[a-zA-Z0-9\s-]+.\z*?

The problem is it still matches when I introduce an invalid character as long as I have a matching sub-string See my REGEX

What can I do to force a match on the whole string? What am I missing?

Thx!

Answer 1

Use ^ (start of line) and $ (end of line) to only match the whole string:

^[a-zA-Z0-9\s-]+.\z*?$

(If you have a multiline input you can also use \A and \z – start and end of string)

On a second look, I don’t understand the end of your regex: . (anything) \z * ? (end of string, zero or more times, zero or one time). This regex will match something like:

Ikdflfdf&

Is that correct? If you only want the character *, you should use:

^[a-zA-Z0-9\s-]+\*?$

Also, as Robbie pointed out, you’re including spaces and the - in your list of accepted characters. If you only want letters and digits, a shortcut would be using \w (word characters):

^\w+\*$

However, depending on whether the matcher is Unicode-aware or not, \w will also match non-ASCII letters and digits, which may or may not be what you want.