Search through NSArray for string

Question

I would like to search through my NSArray for a certain string.

Example:

NSArray has the objects: "dog", "cat", "fat dog", "thing", "another thing", "heck here's another thing"

I want to search for the word "another" and put the results into one array, and have the other, non results, into another array that can be filtered further.

Answer 1

If the strings inside the array are known to be distinct, you can use sets. NSSet is faster then NSArray on large inputs:

NSArray * inputArray = [NSMutableArray arrayWithObjects:@"one", @"two", @"one again", nil];

NSMutableSet * matches = [NSMutableSet setWithArray:inputArray];
[matches filterUsingPredicate:[NSPredicate predicateWithFormat:@"SELF contains[c] 'one'"]];

NSMutableSet * notmatches = [NSMutableSet setWithArray:inputArray];
[notmatches  minusSet:matches];