Microsoft regular expression pattern failed to match

Question

I was trying to use my regex with the options: ignore case, multiline, and ignore white space. But it fails to match. Here's the regex:

"  
\s+(?(U|US|USD)\s*\$\s([a-z0-9$,.'_-]+)(\s[a-z0-9$,.'_-]+)+)\s+(\-\s(Savings|Chequing|\w+)\s(\d{5})\-(\d{7})\s*){0,1}
(Savings|Chequing|\w+)\s(?\d{5}\-(\d{7}))\s+(Available Balance[:]\s[$](?[0-9.,]{3,20})\sUSD\s
[$](?[0-9,.]{3,20}))
"

Here's an example of a string I want to match:

"Close Quick Menu Button
                 U$ smith Hi interest2 
Savings 04237-4500385 Available Balance: $0.00 USD 
$0.00 USD 
Open r"

I think I made mistake is (?<availBal>[0-9.,]{3,20})\\s because the expression matches using the preceding part of the expression

I have been trying with different patterns with no avail.

Your help is much appreciated.

Answer 1

The thing I'm noticing is you have Available Balance right in the middle of your regex.

You need to change that to Available\\sBalance . When it says it ignores whitespace, that means whitespace in the regex not the string you match against.

---

This regex works. I changed the (? to (?: and I added a + .

\s+(?:(U|US|USD)\s*\$\s([a-z0-9$,.'_-]+)(\s[a-z0-9$,.'_-]+)+)\s+(\-\s(Savings|Chequing|\w+)\s(\d{5})\-(\d{7})\s*){0,1}(Savings|Chequing|\w+)\s(?:\d{5}\-(\d{7}))\s+(Available\sBalance[:]\s[$](?:[0-9.,]{3,20})\sUSD\s+[$](?:[0-9,.]{3,20}))

But you're ignoring whitespace, so why not write this legibly? I also changed some unnecessary things you had:

\s+(?:(U|US|USD) \s* \$ \s ([a-z0-9$,.'_-]+)
   (\s[a-z0-9$,.'_-]+)+)
\s+(-\s(Savings|Chequing|\w+)
\s (\d{5})-(\d{7})\s*)?
   (Savings|Chequing|\w+)
\s (?:\d{5}-(\d{7}))
\s+(Available \s Balance: \s \$ (?:[0-9.,]{3,20}) \s USD
\s+\$(?:[0-9,.]{3,20}))