我如何从单独的类访问 getter 和 setter(在 C# 中使用向下转换)

Question

我知道如何在Java中做到这一点，但是C#无法正常工作。我确定我错过了一些明显的东西。如您所见，如果宠物不是狗，我想将宠物扔到狗。我认为沮丧是对的，但也许不是。 问题是这一行Console.WriteLine("{0,12}t {1}t {2,10:C}t {3}t {4}", Name, Type, Price, Weight, Sound(), AKCRegistration);它不允许我访问我所指的 getter。

这是我的主要课程

static void Main(string[] args)
{
Pet[] pets = new Pet[5];
pets[0] = new Dog("King", 55, PET_TYPE.Canine, "akc1000", 1000);
pets[1] = new Dog("Princess", 25, PET_TYPE.Canine, "akc1000", 2000);
pets[2] = new Dog("Spike", 25, PET_TYPE.Canine, "akc1000", 25);
pets[3] = new Cat("Missy", 15, PET_TYPE.Feline, 50);
pets[4] = new Cat("Mr Boogangle", 5, PET_TYPE.Feline, 30);
//for (int i = 0; i < pets.Length; i++)
//{
//    Console.WriteLine($"{pets[i]}");
//}
for each (Pet pet in pets)
{
if (pet is Dog)
{
Dog Pet = (Dog) pet;
Console.WriteLine("{0,12}t {1}t {2,10:C}t {3}t {4}", Name, Type, Price, Weight, Sound(), AKCRegistration);
}
}

这是我的狗课

class Dog: Pet
{
private string aKCregistration;
public Dog(string name, int weight, PET_TYPE type, string AKC, double price) : base(name, weight, type, price)
{
this.aKCRegistration = AKC;
if (aKCRegistration == "")
{
aKCRegistration = "Mutt";
}
}
public int AKCRegistration { get; set; }
public override string Sound()
{
return "Woof, Woof";
}
public override string ToString()
{
return String.Format("{0,12}t {1}t {2,10:C}t {3}t {4}", Name, Type, Price, Weight, Sound());
}
}

我的宠物班

public enum PET_TYPE
{
Canine, Feline
}
public abstract class Pet
{
internal string name;
internal int weight;
internal PET_TYPE type;
internal double price;
public Pet(string name, int weight, PET_TYPE type, double price)
{
this.name = name;
this.weight = weight;
this.type = type;
this.price = price;
}
public string Name
{
get { return name; }
set { name = value; }
}
public int Weight
{
get { return weight; }
set { weight = value; }
}
public double Price
{
get { return price; }
set { price = value; }
}
public PET_TYPE Type
{
get { return type; }
set { type = value; }
}
public override string ToString()
{
return String.Format("{0,12}t {1}t {2,10:C}t {3}t {4}", Name, Type, Price, Weight, Sound());
}
public abstract string Sound();

} // end class pet  

我包括了除我的猫类之外的所有内容，如果您需要查看，请告诉我。

Answer 1

您没有使用实例Pet变量引用它们，在这种情况下，当您从类外部访问它们时，您需要在它们上指定实例变量以告知您正在访问哪个对象的状态，例如：

Console.WriteLine("{0,12}t {1}t {2,10:C}t {3}t {4}", 
Pet.Name, 
Pet.Type, 
Pet.Price, 
Pet.Weight, 
Pet.Sound(), 
Pet.AKCRegistration);

当您在Dog中覆盖ToString成员函数时，您还可以像这样调用它：

string petString = Pet.ToString();

当您访问类中的那些时Dog这意味着您正在引用当前对象，无论哪个调用ToString方法，因此它无需显式指定任何实例即可工作，您可以将其视为：

Console.WriteLine("{0,12}t {1}t {2,10:C}t {3}t {4}", 
this.Name, 
this.Type, 
this.Price, 
this.Weight, 
this.Sound(), 
this.AKCRegistration);

但是我们不需要显式添加this因为编译器会处理这个问题。