How Do I Declare A Block in Objective-C?

最新推荐文章于 2025-11-09 16:10:04 发布
转载 最新推荐文章于 2025-11-09 16:10:04 发布 · 330 阅读 · 0

本文介绍了Objective-C中Block的基本用法，包括作为局部变量、属性、方法参数、方法调用参数及类型定义等不同场景下的使用方式。
转发链接：http://goshdarnblocksyntax.com


As a local variable:


returnType (^blockName)(parameterTypes) = ^returnType(parameters) {...};
As a property:


@property (nonatomic, copy, nullability) returnType (^blockName)(parameterTypes);
As a method parameter:


- (void)someMethodThatTakesABlock:(returnType (^nullability)(parameterTypes))blockName;
As an argument to a method call:


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


typedef returnType (^TypeName)(parameterTypes);
TypeName blockName = ^returnType(parameters) {...};
This site is not intended to be an exhaustive list of all possible uses of blocks.
If you find yourself needing syntax not listed here, it is likely that a typedef would make your code more readable.


Unable to access this site due to the profanity in the URL? http://goshdarnblocksyntax.com is a more work-friendly mirror.
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