【WIP】对象的类型与动态结合

//---------------------------------------------------------------------
//                           类型定义
//---------------------------------------------------------------------
//动态结合与多态
@interface S4_A : NSObject {
    
}
- (void)getLocationOfHierarchy;
- (void)getLocationOfHierarchy:(BOOL)isneedHello;
@end

@interface S4_B : S4_A {
    
}
- (void)getLocationOfHierarchy; //重载
- (void)getLocationOfHierarchy:(BOOL)isneedHello; //重载
@end


//---------------------------------------------------------------------
//                          类定义
//---------------------------------------------------------------------
//动态结合与多态
@implementation S4_A
- (void)getLocationOfHierarchy {
    puts("this is A");
}
- (void)getLocationOfHierarchy:(BOOL)isneedHello {
    if (isneedHello) {
        puts("hello, this is A");
    } else {
        puts("need no hello, this is A");
    }
    
}
@end

@implementation S4_B
- (void)getLocationOfHierarchy {
    puts("this is B");
}
- (void)getLocationOfHierarchy:(BOOL)isneedHello {
    if (isneedHello) {
        puts("hello, this is B");
    } else {
        puts("need no hello, this is B");
    }
}
@end

//---------------------------------------------------------------------
//                             测试函数
//---------------------------------------------------------------------
void S4Tester(void) {
    puts("-----------------------------------------");
    puts("                  S4");
    puts("-----------------------------------------");
    id aTemp = [[S4_A alloc] init];
    [aTemp getLocationOfHierarchy];
    [aTemp getLocationOfHierarchy:NO];
    [aTemp getLocationOfHierarchy:YES];
    
    id bTemp = [[S4_B alloc] init];
    [bTemp getLocationOfHierarchy];
    [bTemp getLocationOfHierarchy:NO];
    [bTemp getLocationOfHierarchy:YES];
    
}

-----------------------------------------
                  S4
-----------------------------------------
this is A
need no hello, this is A
hello, this is A
this is B
need no hello, this is B
hello, this is B
Program ended with exit code: 0