Objective-C 在一个 .h 和 .m 中定义多个类

在Objective-C中，我们可以在一个.h和.m文件中定义多个类。这种方式能够更好地组织和管理代码，提高代码的可读性和可维护性。接下来，我们将通过一个案例来说明如何在一个文件中定义多个类，并展示其用法和优势。

objective-c
#import 
@interface Person : NSObject
@property (nonatomic, strong) NSString *name;
@property (nonatomic, assign) NSInteger age;
- (void)sayHello;
@end

objective-c
#import "Person.h"
@implementation Person
- (void)sayHello {
    NSLog(@"Hello, I'm %@ and I'm %ld years old.", self.name, self.age);
}
@end

objective-c
#import 
@interface Car : NSObject
@property (nonatomic, strong) NSString *brand;
@property (nonatomic, strong) NSString *color;
- (void)drive;
@end

objective-c
#import "Car.h"
@implementation Car
- (void)drive {
    NSLog(@"I'm driving a %@ car with %@ color.", self.brand, self.color);
}
@end

objective-c
#import "ViewController.h"
#import "Person.h"
#import "Car.h"
@implementation ViewController
- (void)viewDidLoad {
    [super viewDidLoad];
    
    Person *person = [[Person alloc] init];
    person.name = @"John";
    person.age = 25;
    [person sayHello];
    
    Car *car = [[Car alloc] init];
    car.brand = @"BMW";
    car.color = @"black";
    [car drive];
}
@end