I want to capture the values of some keys which may be optional, specifically consider the string below
@Foo1:dog|a=5|b=6|c=10|d=12|e=2
@Foo2:cat|a=12|c=10|d=11|e=123
@Foo1:bat|a=213123|b=10
@Foo3:pet|c=346
Now I want to capture the strings between @ and :, : and |, and the value of keys b, d which may be optional. I should the following captured
Foo1, dog, 6, 12
Foo2, cat, 11
Foo1, bat, 10
Foo3, pet
I am using this regex
^@(\w+):(\w+).*(?:b=(\d+)).*(?:d=(\d+)) but it only works when both b and d are present.
You may use
^@(\w+):(\w+)(?:.*?\|b=(\d+))?(?:.*?\|d=(\d+))?
See the regex demo
Details
^ - start of string@ - a @ char(\w+) - Group 1: one or more word chars: - a colon(\w+) - Group 2: one or more word chars(?:.*?\|b=(\d+))? - an optional non-capturing group matching any 0+ chars other than line break chars, as few as possible, then |b= and then capturing 1+ digits into Group 3(?:.*?\|d=(\d+))? - an optional non-capturing group matching any 0+ chars other than line break chars, as few as possible, then |d= and then capturing 1+ digits into Group 4