黑馬程式設計師Objective-C筆記:封裝,繼承,多型
阿新 • • 發佈:2019-02-10
例子: #import @interface Animal : NSObject - (void)eat; @end @implementation Animal - (void)eat { NSLog(@"Animal---Eating something!!"); } @end @interface Dog : Animal @end @implementation Dog - (void)eat { NSLog(@"Dog--Eating something!!"); } @end int main() { //多種形態 // Dog *d = [Dog new]; //Dog型別 Animal *a = [Dog new]; //呼叫一個物件方法時,呼叫的是真實物件方法 // NSObject *n = [Animal new]; [a eat]; return 0; } 輸出結果為:Dog--Eating something