@property以及@synthesize的用法

#import <UIKit/UIKit.h>

@interface PropertyViewController : UIViewController {
    NSInteger Number1;
    NSInteger Number2;
}
@property NSInteger Number1;
@property NSInteger Number2;
@end

#import "PropertyViewController.h"
@implementation PropertyViewController

@synthesize Number1, Number2;

// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
    [self setNumber1: 1];
    [self setNumber2: 2];
    
    NSLog(@"Number1:%d\nNumber1 + 2:%d", [self Number1], Number1 + 2);
    NSLog(@"Number2:%d\nNumber2 + 2:%d", [self Number2], Number2 + 2);
    [super viewDidLoad];
}

- (void)dealloc {
    [super dealloc];
}
@end

用了@property 特性自动生成setter和getter方法。