Get a list of all available Objective-C Class objects whose names match a predicate #objective-c #advanced #runtime #dynamic

objc_filtered_class_objects.m

+ (NSArray *)arrayOfClassObjectsFilteredByPredicate:(NSPredicate *)predicate
{
    int numClasses;
    Class *classes = NULL;
    
    classes = NULL;
    numClasses = objc_getClassList(NULL, 0);
    
    if (numClasses < 1 ) return nil;
    
    classes = (__unsafe_unretained Class *)malloc(sizeof(Class) * numClasses);
    numClasses = objc_getClassList(classes, numClasses);
    
    // Convert to NSArray of NSStrings
    NSMutableArray *rtn = [[NSMutableArray alloc] init];
    const char *cname;
    for (int i=0; i<numClasses; i++) {
        cname = class_getName(classes[i]);
        if ([predicate evaluateWithObject:[NSString stringWithCString:cname encoding:NSStringEncodingConversionAllowLossy]]) {
            [rtn addObject:classes[i]];            
        }
    }
    free(classes);
    
    return rtn;
}