NSPredicate 'OR' filtering based on an NSArray of keys
- by So Over It
Consider the following NSArray:
NSArray *dataSet = [[NSArray alloc] initWithObjects:
[NSDictionary dictionaryWithObjectsAndKeys:@"abc", @"key1", @"def", @"key2", @"hij", @"key3", nil],
[NSDictionary dictionaryWithObjectsAndKeys:@"klm", @"key1", @"nop", @"key2", nil],
[NSDictionary dictionaryWithObjectsAndKeys:@"qrs", @"key2", @"tuv", @"key3", nil],
[NSDictionary dictionaryWithObjectsAndKeys:@"wxy", @"key3", nil],
nil];
I am able to filter this array to find dictionary objects that contain the key key1
// Filter our dataSet to only contain dictionary objects with a key of 'key1'
NSString *key = @"key1";
NSPredicate *key1Predicate = [NSPredicate predicateWithFormat:@"%@ IN self.@allKeys", key];
NSArray *filteretSet1 = [dataSet filteredArrayUsingPredicate:key1Predicate];
NSLog(@"filteretSet1: %@",filteretSet1);
Which appropriately returns:
filteretSet1: (
{
key1 = abc;
key2 = def;
key3 = hij;
},
{
key1 = klm;
key2 = nop;
}
)
Now, I am wanting to filter the dataSet for dictionary objects containing ANY of the keys in an NSArray.
For example, using the array: NSArray *keySet = [NSArray arrayWithObjects:@"key1", @"key3", nil]; I want to create a predicate that returns and array of any dictionary objects that contain either 'key1' or 'key3' (ie. in this example all dictionary objects would be returned except for the third object - as it does not contain either 'key1' or 'key3').
Any ideas on how I would achieve this? Would I have to use a compound predicate?
