objective-c（接口&实现）

#import <Foundation/Foundation.h> //基础库，类似C中的stdlib

typedef enum eType {type1 = 1,type2,type3} ETYPE; //OC中对enum、#define、typedef的使用与在C中基本无差异

@interface Teacher : NSObject{
    int tid;
    NSString *name;
    ETYPE type;
}

//peoperty定义这个类的属性，这些属性替代了java中getXXX的方法；
@property int tid;
@property NSString *name;
@property ETYPE type;

-(void) setName: (NSString*)name andId:(int)tid andType:(ETYPE)type;
-(void) print;

@end

#import "Teacher.h"

#import <Foundation/Foundation.h>

@implementation Teacher

@synthesize tid,name,type; //标示所声明的属性

-(void)setName:(NSString *)inputname andId:(int)inputtid andType:(ETYPE)inputtype{
    self.tid  = inputtid; //self相当于this
    self.name = inputname;
    self.type = inputtype;
}

-(void) print{
    NSLog(@"%@ and %i and type %i", self.name,self.tid,self.type);   
}

@end

#import <Foundation/Foundation.h>
#import "Student.h"
#import "Teacher.h"

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        
        Student *tmp1 = [[Student alloc]init];
        [tmp1 setName:@"fredric" andId:18];
//id object
        id data； //指向NSObject的指针，下面这个例子可以实现类似多态的功能    
        data = tmp1;
        [data print];        
    }
    return 0;
}