__weak NSString *strin = [[NSString alloc] initWithFormat:@"hey"] ;
NSLog(@"weak %@",strin); //returns weak (null)
__weak NSString *strin =@"hey";
NSLog(@"weak %@",strin); //returns weak hey
What is the difference between both the snippets. Why the second is returning the value when weak is assigned ?
这是因为@"hey"
是一个常量字符串文字,它将永远存在,而对第一个(已分配)字符串的弱引用不足以使其保持活动状态。
Check below snap and you will get your answer your self.
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