Question

NSString *myText = @"mary had a little lamb";
NSString *regexString = @"mary(.*?)little";

for(NSString *match in [myText captureComponentsMatchedByRegex:regexString]){

NSLog(@"%@",match);

}

This will output to the console two things:

1) “mary had a little”
2) “had a”

What I want is just the 2nd bit of information “had a”. Is there is a way of matching a string and returning just the inner part?

I’m fairly new to Objective C, this feels a rather trivial question yet I can’t find a less messy way of doing this than incrementing an integer in the for loop and on the second iteration storing the “had a” in an NSString.

Answer 1

With regular expressions, it’s standard that the first match returned is the whole matched string (“mary had a little”), then the next items are the captured groups (“had a”).

-captureComponentsMatchedByRegex: returns a NSArray of the matches. So, if you want the second item, or the first captured group:

NSString *match = [[myText captureComponentsMatchedByRegex:regexString] objectAtIndex:1]