Question

Possible Duplicate:
Why use 'self.' when its not forced?

What is the difference between these 2 blocks of code?

@property (nonatomic, retain) MyObject *myObject;

MyObject *obj = [[MyObject alloc] init];
self.myObject = obj;
[obj release];

MyObject *obj = [[MyObject alloc] init];
myObject = obj;
[obj release];

EDIT:

Does it mean that on the second block I don’t need to release “obj” ?

Answer 1

In the first case, self.myObject implies that myObject is a @property, and when you assign to it with self.myObject = obj, that property’s setter will get invoked. Often, that setter is automagically generated by the compiler with the @synthesize directive. If that property’s autogenerated setter is flagged with retain, then whatever assigned to it (in this case, obj) will be retained by the property.

In the second case, myObject may or may not be a property. Regardless, this is a simple assignment. No retain is done.