Arc Object memory management and strength pointers

_strong person *p Strong pointer

_weak person *p Weak pointer

Person *p strong pointer, default is strong pointer

Single Object

As long as there is no object pointed to by a strong pointer in arc, the memory is freed

_weak person *p=[[person Alloc]init];

It will be released when it is created.

Multi-Object

People have dogs.

@property (Nonaatomic,strong) Dog *dog;

When the dog is released separately, dog is not necessarily released because it is possible that the person's property has a pointer pointing to the dog

When pointing at each other

People have dogs.

@property (Nonaatomic,strong) Dog *dog;

The dog has a master

@property (nonaatomic,weak) person *person;

One side must use a weak pointer, or it will never be released

Arc Object memory management and strength pointers