Dynamically find available Objective-C classes

objc_getClassList give you a list of all available classes by asking the ObjC runtime.

Don’t forget to import to runtime (#import <objc/runtime.h>) and link to it (libobjc.dylib).

You can then do funny things; for example: finding classes with a name matching a specific pattern with a block:

NSArray* getClassesMatching(BOOL(^block)(NSString *className)) {
NSMutableArray *array = [NSMutableArray array];

int numClasses;
Class * classes = NULL;

classes = NULL;
numClasses = objc_getClassList(NULL, 0);

if (numClasses > 0 ) {
    classes = malloc(sizeof(Class) * numClasses);
    numClasses = objc_getClassList(classes, numClasses);

    Class class = nil;
    for (int i = 0; i < numClasses; i++) {
        class = classes[i];

        if (block([NSString stringWithCString:class_getName(classes[i]) encoding:NSUTF8StringEncoding])) {
            [array addObject:class];
        }
    }
    free(classes);
}
return [array copy];
}