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What is KVC and KVO? Give an example of using KVC to set value.

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Key-Value-Coding (KVC) means accessing a property or value using a string. id someValue = [myObject valueForKeyPath:@”foo.bar.baz”];

Which could be the same as:

id someValue = [[[myObject foo] bar] baz];

Key-Value-Observing (KVO) allows you to observe changes to a property or value.

To observe a property using KVO you would identify to property with a string; i.e., using KVC. Therefore, the observable object must be KVC compliant.

[myObject addObserver:self forKeyPath:@”foo.bar.baz” options:0 context:NULL];

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