IOS-day03_OC中的get和set

1 @interface Car : NSObject
2 {
3     int wheels;
4 }
5 
6 -(void) run;
7 -(void) setWheels:(int)newWheels;
8 -(int) wheels;
9 @end

 1 @implementation Car
 2 
 3 -(void)run{
 4     NSLog(@"%i个轮子的车跑起来了",wheels);
 5 }
 6 -(void) setWheels:(int) newWheels{
 7     if (newWheels <= 0) {
 8         newWheels = 4;
 9     }
10     wheels = newWheels;
11 }
12 -(int) wheels{
13     return wheels;
14 }
15 @end