What are kvc and kvo? Provide an example.
Answer / Bhaskar Narayan
In Objective-C, Key-Value Coding (KVC) and Key-Value Observing (KVO) are design patterns for dynamic runtime behavior. KVC allows you to access instance variables and call methods on objects using strings instead of fixed property names. KVO enables you to observe changes to an object's properties automatically. Here is a simple example of KVC: NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys:@"John", @"name", @30, @"age", nil]; NSString *value; value = [dict objectForKey:@"name"]; // returns John. Example of KVO: You can observe changes to an object's properties using NSKeyValueObserving protocol.
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