Hi, 

I have tried and I am unable to find a way. I have a list of country phone codes and the country. For example +44 = United Kingdom.

I had written a workflow rule, however due to limitations it ended up being around 10k characters and it is too large for the workflow. Is there a way to do this using an apex trigger and if so would someone be able to help me with the structure? 

It would need to search in a list the country code and populate a country field with the respective country.