oc中的block使用心得

typedef   void (^ simpleBlock) (void);

typedef  double (^multiplyTwoValues)(double, double);

typedef   void (^ simpleTestBlock) (int ,int);

@implementation TJAppDelegate



- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions

{

    // Override point for customization after application launch.

     simpleBlock block =^{

        NSLog(@"this is a block");

    

    };

    

   block();

    multiplyTwoValues values=^(double x,double y)

    {

        

        return x *y;

    };

    NSLog(@"%.3f",values(2.0,3.0));

    simpleTestBlock  testBlock=^(int x,int y)

    {

        NSLog(@"--->%d",x+y);

    };

    testBlock(2,3);

    

    return YES;

}