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Regex to find a string that does not contain a space while matching other conditions

I have a bunch of strings that may contains certain patterns. Specifically, the following 3.
Starts with (- followed by 10 digits followed by ).
E.g.:
(-1234567890)
Starts with (, ends with ), and may contain 1 or more characters, but NO spaces.
E.g.:
(ABC) or (AF33) or (2345)
Starts with (, ends with ), and may contain 1 or more characters, INCLUDING spaces.
E.g.:
(Some string)
The strings I work with may contain zero or more of the patterns above. My requirement is to match ONLY the second one from above in a given string, and I'd like to be able to use Regex class in C#.
For example, let's say following are five different strings I have.
This is some random text.
This is some (ABC) random (-1234567890) text.
This is some (XY12) random (-1234567890) text.
This is some (Contains space) random (-1234567890) text.
This is some () random text.
My Regex should match only the 2nd and 3rd strings from the above list.
So far, I've managed to write this following Regex, which excludes strings 1 and 5.
.*\((?!\-).+\).*
This matches 2nd, 3rd, AND 4th strings above. Now I'm not sure how I can get it to exclude the 4th, one which contains spaces inside parenthesis. I know that \S detects whitespaces, but how can I tell it to detect strings that do not contain spaces only within the parenthesis that don't contain a - after the first (?
EDIT 1:
There will never be nested parenthesis in my strings.
EDIT 2:
Here's a Regex Tester.

.*\(\w+\).*
If you use above regex, second and third strings are matches only
.* all characters
( pharantesis
\w+ all word characters (at least one)
) pharantesis
.* all characters

\(([^- ]+[^ ]*)\)
should work
Explanation:
[^- ]+ will first match one character that's neither - or This will make sure it contains at least one character
Then [^ ]* will match 0 or more none white space characters
This will work for any char set

C# Regex boundary with special characters

I want to have a Regex that finds "Attributable".
I tried #"\bAttributable\b" but the \b boundary doesn't work with special characters.
For example, it wouldn't differentiate Attributable and Non-Attributable. Is there any way to Regex for Attributable and not it's negative?

Do a negative look-behind?
(?<!-)\bAttributable\b
Obviously this only checks for -s. If you want to check for other characters, put them in a character class in the negative look-behind:
(?<![-^])\bAttributable\b
Alternatively, if you just want to not match Non-Attributable but do match SomethingElse-Attributable, then put Non- in the look-behind:
(?<!Non-)\bAttributable\b

There are several ways to fix the issue like you have but it all depends on the real requirements. It is sometimes necessary to precise what "word boundary" you need in each concrete case, since \b word boundary is 1) context dependent, and 2) matches specific places in the string that you should be aware of:
Before the first character in the string, if the first character is a
word character.
After the last character in the string, if the last
character is a word character.
Between two characters in the string,
where one is a word character and the other is not a word character.
Now, here are several approaches that you may follow:
When you only care about compound words usually joined with hyphens (similar #Sweeper's answer): (?<!-)\bAttributable\b(?!-)
Only match between whitespaces or start/end of string: (?<!\S)Attributable(?!\S). NOTE: Actually, if it is what you want, you may do without a regex by using s.Split().Contains("Attributable")
Only match if not preceded with punctuation and there is no letter/digit/underscore right after: (?<!\p{P})Attributable\b
Only match if not preceded with punctation symbols but some specific ones (say, you want to match the word after a comma and a colon): (?<![^\P{P},;])Attributable\b.

Repeating pattern matching with Regex

I am trying to validate an input with a regular expression. Up until now all my tests fail and as my experience with regex is limited I thought someone might be able to help me out.
Pattern: digit (possibly "," digit) (possibly ;)
A String may not begin with a ; and not end with a ;.
Digits are allowed to stand alone or with
My regEx (not working): ((\d)(,\d)?)(;?) the problem is it does not seem to check until the end of the string. Also the optional parts are giving me headaches.
Update: ^[0-9]+(,[0-9])?(;[0-9]+(,[0-9])?)+$this seems to work better but it does not match the single digit.
OK:
2,3;4,4;3,2
2,3
2
2,3;3;4,3
NOK:
2,3,,,,
2,3asfafafa
;2,3
2,3;;3,4
2,3;3,4;

Your ^[0-9]+(,[0-9])?(;[0-9]+(,[0-9])?)+$ regex matches 1 or more digits, then an optional sequence of , and 1 digit, followed with one or more similar sequences.
You need to match zero or more comma-separated numbers:
^\d+(?:,\d+)?(?:;\d+(?:,\d+)?)*$
^
See the regex demo
Now, tweaking part:
If only single-digit numbers should be matched, use ^\d(?:,\d)?(?:;\d(?:,\d)?)*$
If the comma-separated number pairs can have the second element empty, add ? after each ,\d (if single digit numbers are to be matched) or * (if the numbers can have more than one digit): ^\d(?:,\d?)?(?:;\d(?:,\d?)?)*$ or ^\d+(?:,\d*)?(?:;\d+(?:,\d*)?)*$.

Regex to capture an exact word in a sentence

I'm having some trouble to capture a specific string inside of a sentence.
The Regex I'm using is \b[0-9]{9,12}\b to capture numbers which have between 9 and 12 digits. The boundary I was using it to specify the exact number, but the problem is, when I have a number which matches with this regex followed by a dot, for example, the regex still matching and giving me much trouble.
As I searched, the problem is that \b uses some special characters as a separator too, right? Then is there a way to consider, for example 123456789. a whole string and the regex will not match with that example?
Thanks !

The word boundary \b requires a non-word character before and after a digit (as a digit is a word character). As dots and commas are non-word characters, they are allowed. To make sure the digit sequence between dots is not matched, you need to use lookarounds.
You can use
\b(?<!\.)[0-9]{9,12}(?!\.)\b
See the regex demo
The additional subpatterns are the lookbehind (?<!\.) and a lookahead (?!\.) that make sure there are no . before and after the digit sequence.
If you have . and , as decimal separators, you may want to adjust the pattern to
\b(?<![.,])[0-9]{9,12}(?![.,])\b

Regex to match trimmed string consisting of words separated by only 1 space char

I am looking for a regex to validate input in C#. The regex has to match an arbitrary number of words which are separated with only 1 space character in between. The matched string cannot start or end with whitespace characters (this is where my problem is).
Example: some sample input 123
What I've tried: /^(\S+[ ]{0,1})+$/gm this pattern almost does what is required but it also matches 1 trailing space.
Any ideas? Thanks.

I tried this one and it seems to work:
Regex regex = new Regex(#"^\S+([ ]{1}\S+)*$");
It checks if your string starts with a word followed by zero or more entities of a single white space followed by a word. So trailing white spaces are not allowed.