Regex to replace timezone offset

Question

I have a string representing date/time with timezone. I want to change the timezone part to UTC that is +00:00

Please help me to write regext to match +05:30, -03:30 etc and replace it with +00:00

I tried with "2012-04-17T15:40+05:30".gsub!(/\+\d\d:\d\d/, '+00:00') which gives me expected results but I don't know how to match -5:30

I would appreciate if someone helps me to write regex which work with both 2012-04-17T15:40+05:30 and 2012-04-17T15:40-05:30

Thanks, Amit Patel

Answer 1

"2012-04-17T15:40+05:30".gsub!(/[+-]\d\d:\d\d/, '+00:00')

will replace both positive and negative offsets. But why?

Answer 2

How about simple:

str = "2012-04-17T15:40+05:30"
str.sub!(/.{6}\z/, '+00:00') # => "2012-04-17T15:40+00:00"