Why should I not use object_setIvar to set properties

I have a dictionary containing data for user from a REST endpoint. Here is my user class

#import <Foundation/Foundation.h>

@interface User : NSObject

@property (strong, nonatomic) NSString *uid;
@property (strong, nonatomic) NSString *email;
@property (strong, nonatomic) NSString *firstName;
@property (strong, nonatomic) NSString *lastName;
@property (assign, nonatomic) int status;

@end

I have a method to set all properties

/*
 * set properties
 */
- (void)setPropertiesWithDictionary:(NSDictionary *)dictionary{
    for(NSString *key in dictionary){

        object_setIvar(self,
                       class_getInstanceVariable([self class], [[@"_" stringByAppendingString:key] UTF8String]),
                       dictionary[key]);
    }
}

Instead of doing something like [user setUid:@dictionary[@"uid"]];

I want to call my method like this [user setPropertiesWithDictionary: dictionary];

Just wondering if implementing object_setIvar this way is fine. If not - Would be really great if you can explain why. Thanks in advance.

Solution

Do whatever you like, but why reinvent the wheel when key value coding (KVC) already exists? Just call this method:

https://developer.apple.com/documentation/objectivec/nsobject/1417515-setvaluesforkeyswithdictionary?language=objc

KVC does what you're trying to do, but it does it a lot better than you're likely to do it.

https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/KeyValueCoding/index.html