Regex to match Number of 1-3 Digits After a Known String in Ruby

Question

I need to match the numbers in the following strings. It is possible they may be part of longer strings with other numbers in them, so I specifically want to match the number(s) occuring directly after the space which follows the text 'Error Code':

Error Code 0  # Match = 0
Error Code 45 # Match = 45
Error Code 190 # Match = 190

Also possible:

Some Words 12 Error Code 67 Some Words 77 # Match = 67

I'm using someString.match(regEx)[0] but I can't get the regex right.

Answer 1

/(?:Error Code )[0-9]+/

This uses a non-capturing group (not available in all regex implementations.) It will say, hey the String better have this phrase, but I don't want this phrase to be part of my match, just the numbers that follow.

If you only want between 1 and three digits matched:

/(?:Error Code )[0-9]{1,3}/

With Ruby you should run into very few limitations with your regex. Aside from conditionals, there isn't very much Ruby's regex cannot do.

Answer 2

Given the string "Error Code 190", this will return "190" and not "Error Code" like the other regex example provided here.

(?<=Error Code.*)[0-9]