定义block块

一: 工程图

二: 代码区

AppDelegate.h

#import <UIKit/UIKit.h>
 
@interface AppDelegate : UIResponder <UIApplicationDelegate>
 
@property (retain, nonatomic) UIWindow *window;
 
//@property (strong, nonatomic) UIWindow *window;
 
@end

AppDelegate.m

#import "AppDelegate.h"
 
@interface AppDelegate ()
 
@end
 
#pragma mark - 定义有返有参block块并重命名
typedef int (^SUM)(int , int);
 
#pragma mark - 定义无返无参block块并重命名
typedef void (^LOVE)();
 
@implementation AppDelegate
- (void)dealloc
{
    self.window = nil;
 
    [super dealloc];
}
 
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
    // Override point for customization after application launch.
 
#pragma mark - 有返有参block块调用方法
    SUM sum1 = ^(int a , int b) {
 
        return a + b;
    };
 
    NSLog(@"%d" , sum1( , ));
 
#pragma mark - 有返有参block块调用方法
    LOVE love = ^() {
 
        NSLog(@"I Love You!");
    };
 
    love();
 
    self.window.backgroundColor = [UIColor whiteColor];
    [self.window makeKeyAndVisible];
    return YES;
}
 
@end