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block捕获变量的几道测试题

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第一题

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NSInteger age = 20;
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    void(^block)() = ^(){
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        NSLog(@"%li",age);//打印的值为几
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    };
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    age = 40;
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    block();

第二题

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SCPerson *person = [[SCPerson alloc]init];
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    person.age = 20;
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    void(^block)() = ^(){
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        NSLog(@"%li",person.age);//打印的值为几
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    };
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    person.age = 40;
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    block();

第三题

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SCPerson *person = [[SCPerson alloc]init];
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    person.age = 20;
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    void(^block)() = ^(){
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        NSLog(@"%li",person.age);//打印的值为几
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    };
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    person = [[SCPerson alloc]init];
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    person.age = 40;
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    block();

第四题

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    SCPerson *person = [[SCPerson alloc]init];
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    person.age = 20;
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    __weak SCPerson *weakPerson = person;
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    void(^block)() = ^(){
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        NSLog(@"%li",weakPerson.age);//打印的值为几
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    };
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    person = [[SCPerson alloc]init];
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    person.age = 40;
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    block();

第五题

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SCPerson *person = [[SCPerson alloc]init];
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    person.age = 20;
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    __weak SCPerson *weakPerson = person;
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    void(^block)() = ^(){
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        __strong SCPerson *strongPerson = weakPerson;
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        NSLog(@"%li",strongPerson.age);//打印的值为几
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    };
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    person = [[SCPerson alloc]init];
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    person.age = 40;
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    block();