Question

I need to validate a string to allow only a specific set of characters using regex. Unfortunately, I am stuck using regex only for the validation of these strings.

Anyways I need to limit a string to allow only the following characters:
a-z and A-Z and 0-9 and space and .,;:!=+-_

For this I have created the following expression:

[a-zA-Z0-9.,;:!=+-_\s]*

I can’t figure out why this expression is not working. The following test strings when I am using this are giving me the following results:

<test> Valid 
$<test> Invalid 
test Valid 
<test>asdf</test> Invalid

It appears the order of these special characters is being taken into account when really all I need to to limit the validation to a specific list of valid characters regardless of the order in the string.

Can anyone shed some light on why this may be allowing special characters such as ‘<>’ but only in certain orders?

Answer 1

use anchors and shild symbol -

^[a-zA-Z0-9.,;:!=+\-_\s]*$