自我会保留在块内吗? [英] Will self retain within block?

问题描述

在调用该块之前/之后，保留计数始终为1. 来自苹果阻止文档，我们知道自己应该保留.谁能知道为什么吗?

Before/After call the block, the retaincount is always 1. From apple block doc we know that the self should retain. Can anyone know why?

NSLog(@"Before block retain count: %d", [self retainCount]);    
void (^block)(void) = ^(void){
    UIImage* img = [UIImage imageNamed:@"hometown.png"];
    [self setImage:img];
    NSLog(@"After block retain count: %d", [self retainCount]);
};
block();

推荐答案

首先， retainCount没有用.不要叫它..

块仅在复制块时保留捕获的对象.因此，该示例中的块不会保留self.

Blocks only retain captured objects when the block is copied. Thus, self won't be retained by the block in that example.

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