How to determine class of Objective-C Property?

Question

Ok, so say I have a property on a class:

@interface MyObject : NSObject {
    MyOtherObject *someOtherObject;
}

@property (nonatomic, copy) MyOtherObject *someOtherObject;

@end

I'm trying to create something to deserialize an API response into the correct objects without explicitly defining what class each api attribute maps to. So, is there any way for me to find out what class a property is, even if it's nil? What I'm looking for is some method like [MyObject classForProperty:@"someOtherObject"] which would return a Class object. Note--I'm not looking for isKindOfClass: or just class, as those won't work on a nil value.

Worst case, I can just manually define a list of property classes, but it'd be really nice if there were some built in way to do it.

Answer 1

Ok, I ended up figuring this out after coming across this question: In Objective-C Determine if a Property is an int, float, double, NSString, NSDate, NSNumber, etc

Here's the code:

@interface NSObject (Properties)

+ (Class)classForProperty:(NSString *)propertyName;

@end

#import <objc/runtime.h>

@implementation NSObject (Properties)

+ (Class)classForProperty:(NSString *)propertyName {
    const char *attributes = property_getAttributes(class_getProperty([self class], [propertyName UTF8String]));
    NSString *attributesString = [NSString stringWithUTF8String:attributes];
    NSArray *parts = [attributesString componentsSeparatedByString:@","];
    NSString *typeString = [[parts objectAtIndex:0] substringFromIndex:1];

    if ([typeString hasPrefix:@"@"] && [typeString length] > 1) {
        NSString *name = [typeString substringWithRange:NSMakeRange(2, [typeString length]-3)];
        Class theClass = NSClassFromString(name);
        return theClass;
    }

    return nil;
}

@end

It seems to work pretty well for me, but any modifications are definitely welcome.