How Do I Declare A Block in Objective-C?

標籤：

How Do I Declare A Block in Objective-C?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.

By Mike Lazer-Walker, who has a very bad memory for this sort of thing.

How Do I Declare A Block in Objective-C?