View the reference count of an object under ARC, and the reference count of an arc object

View the reference count of an object under ARC, and the reference count of an arc object

The conclusions of various online articles and Q & A are "reference count values of objects cannot be printed under ARC ".

Indeed, ARC prohibits you from directly viewing the reference count of the Objective-C object, but can the Objective-C object still be converted to a Core Foundation object? So I started a small experiment:

Id obj = [[NSObject alloc] init]; printf ("retain count = % ld \ n", CFGetRetainCount (_ bridge CFTypeRef) (obj )));

Note that _ bridge is used for conversion. If _ bridge_retained is used for conversion, a Core Foundation object is generated, and retain the original Objective-C object, causing the reference count to be greater than the actual value.

Running result

Retain count = 1

The project has enabled the ARC mode and correctly outputs the reference count value of the OC object.