Is there a way construct a predicate to filter by class type?
I currently loop through the array and check to the class of each object. Maybe there is a cleaner way?
You can directly compare classes as well in your predicate.
But, it probably won't work as you would expect if you're trying to filter for objects that belong to class clusters or if you have subclasses.
For example, NSDate
when instantiated is usually an __NSCFDate
and NSString
can be NSCFString
as well as other specific private classes.
It's probably better to just loop through the set yourself and use -isKindOfClass:
as the test.
IF you really want to use NSPredicate
though you can do this. As an example, this would filter an array for all objects derived from NSString
. If you wanted strict class membership you could replace isKindOfClass:
with isMemberOfClass:
.
Any selector that all objects in the collection implement, takes one argument and returns a BOOL
should work though.
NSArray *mixedArray = {...};
NSPredicate *predicate = [NSPredicate predicateWithFormat:
@"self isKindOfClass: %@",
[NSString class]];
NSLog(@"%@", [mixedArray filteredArrayUsingPredicate:predicate]);