09 多态

Tags: Objective-C

---

多态直接贴代码解释吧，跟C++差不多。
GKHBase.h

#import <Foundation/Foundation.h>@interface GKHBase : NSObject- (void) base;- (void) test;@end

GKHBase.m

#import "GKHBase.h"@implementation GKHBase- (void) base {    NSLog(@"这是父类的base方法");};- (void) test {    NSLog(@"这是父类的test方法");}@end

GKHSub.h

#import <Foundation/Foundation.h>#import "GKHBase.h"@interface GKHSub : GKHBase- (void) sub;@end

GKHSub.m

#import "GKHSub.h"@implementation GKHSub- (void) sub {    NSLog(@"这是子类的sub方法");}@end

main.m

#import <Foundation/Foundation.h>#import "GKHSub.h"int main(int argc, const char * argv[]) {    @autoreleasepool {        GKHBase *bc = [[GKHBase alloc] init];        [bc base];        [bc test];        GKHSub *sc = [[GKHSub alloc] init];        [sc base];        [sc test];        [sc sub];        //多态实现        GKHBase *bc1 = [[GKHSub alloc] init];        [bc1 base];        [bc1 test];        //因为bc1的编译类型是GKHBase，该类并没有提供sub方法，所以会导致编译错误        //[bc1 sub];        id bc2 = bc1;        [bc2 sub];        //isKindOfClass:clazz方法判断对象是否是clazz或其子类的实例        NSLog(@"sc是否是GKHBase类及其子类的实例：%d", [sc isKindOfClass:[GKHBase class]]);        NSLog(@"sc是否是GKHSub类及其子类的实例：%d", [sc isKindOfClass:[GKHSub class]]);    }    return 0;}