Regular expression validators

Question

I am using Regular expression validator  during the create transition.

I am using [a-zA-Z0-9_=+-] because I need to allow special charterers (_,+,-,=, ).

Am I doing something wrong because this is not working and throwing error whenever i place '_' symbol.

KALYAN CHAKRAVARTHY THADAKA · Answer

While using regular expression to validate input data from user.

So, what ever you wrote a regular expression in attributes should enclosed by parenthesis.

For example:

([A-Za-z0-9+_= -]*)

Vineela Durbha · Answer

No it was not working.

I tried to do as below and it is working

[A-Za-z0-9+_= -]*

Andy Heinzer · Answer

Sometimes you need to escape certain characters in order to have regex search for them. Since the syntax can be a little different depending on the interpreter.  Instead of using your string of

[a-zA-Z0-9_=+-]

try this one

[a-zA-Z0-9\_\=\+\-]

The character of '\' can be used to tell a regex to search specifically for the next character and not use that character's special regex function.   I don't know of any special function for the _ character in regex, but I think you can still try to escape it incase it is causing this to fail to match a character set you are looking for.