I want to search all '2' s in the string below:
2, 10,11,1,1, 22,1,12,1,1, 1,2 , 2 ,2
I gave regular expression:
(^\s*(2)\s*)|(\s*,\s*(2)\s*(,|$))
But it will not search last but one 2.
I changed regular expression now as,
(^\s*(2)\s*)|(\s*,\s*(2)\s*)
But now it will take one of the 2s in 22.
How can I change the regular expression so that I find all the 2s (22 or 12 should not be considered)?
This will match all the standalone 2 in the input string:
(?<!\d)2(?!\d)
The regex above is equivalent to the following regex, as in it will always have the same number of matches, and the content of the capturing group 1 in this regex is the same as the content matched by the other regex:
(?:^|\D)(2)(?:\D|$)
Note that (both) regex above doesn't care about the format of the input. It just simply extract any standalone 2, even in:
2 plain text, 2,43_2,lkjsf
^ ^ ^
If you want to match columns with the value 2, and disregard 2 in 2 2 or abc 2:
(?:^|,) *(2) *(?=,|$)
It will match the only the 2 in this sample text:
2 plain text, 2 ,2, 43_2, 2 2,2 ,234,2
^ ^ ^ ^