这篇文章在只是列了在平时代码中block的写作方式, 仅仅是作为备忘

• 作为局部变量

returnType (^blockName)(parameterTypes) = ^returnType(parameters) {...};

• 作为属性

@property (nonatomic, copy, nullability) returnType (^blockName)(parameterTypes);

• 作为方法变量

- (void)someMethodThatTakesABlock:(returnType (^nullability)(parameterTypes))blockName;

• 作为方法参数

[someObject someMethodThatTakesABlock:^returnType (parameters) {...}];

• typedef
  • 使用typedef可以让block在代码中跟易读

typedef returnType (^TypeName)(parameterTypes);
TypeName blockName = ^returnType(parameters) {...};