Regex for backslash

[prach Gupta]

Hi
I am trying to have backslash(\) in my expression.Its an escape character but for its own use in an expression,I am unable to find a solution.I have tried "\\\\" but it doesnt accepts it.

[Colin Brewster]

Hi

\\ should match \, basically you are escaping the backslash itself.

If you need the expression as a string in code you will need to use "\\\\"

[Campbell Ritchie]

"\\" ???

[Colin Brewster]

\\ matches the backslash character, so for example if the expression is entered from a console that would match. However if the pattern is created from a string literal then you would need "\\\\" (double backslashes are required for a backslash in string literals).

[prach Gupta]

Colin,
I am trying the regex "\\\\" only but it doesnot seem to work.I have tried it many a times but it is taken as an invalid character.

[Colin Brewster]

Hi Prach

Could you post some sample code showing your problem? "\\\\" works fine for me.

Thanks

[prach Gupta]

Hi
My Requirement is ---Only the following characters are allowed in integer fields:
0 - 9, ( ) + <space> , - / \
and the regex that I have used is "^\\+?[0-9\\(?\\)\\s\\-\\,\\/]*" which works fine but if I add "\\\\" into it for validation of backslash ,invalid character error is thrown.

[Colin Brewster]

Hi

I'm not sure why that isn't working for you, it looks fine to me although there are a few unnecessary escapes and a rogue "?" in the expression you posted, though for me they dont cause any exception to be thrown.

This is a slightly cleaner version of your expression that works fine for me: "^\\+?[-0-9]()\\s,-/\\\\]*"

If you just use "\\\\" on it's own do you still get the exception? Maybe it's environmental?