iOS 我的block笔记

.h里面

#import <UIKit/UIKit.h>

typedef NSString *(^square)(int,float,NSString *);//注意此处

@interface BlockTestVC :
UIViewController

@end

.m里面

- (void)viewDidLoad

{

[super
viewDidLoad];

square square1 = ^(int a,float b,NSString *c){

NSString *test = [NSString
stringWithFormat:@"%d+%f=%@",a,b,c];

return test;

};

[self test:square1];

}

-(void)test:(square)squ {

NSString *testStr = squ(6,6.66,@"大顺");//回调，并获取返回值

NSLog(@"%@",testStr);

}