C＃將類類型傳遞給基本構造函數

Question

好吧，這是一個 盤繞 /復雜的問題，在這里：

• 我有兩節課
  • Derived類繼承自Base類（ class Derived: Base{} ）
  • Class2從Class1繼承（ class Class2: Class1 {} ）

我當前的Class1構造函數具有：

Derived d = new Derived();

我想要的是將Derived類型從Class2構造函數傳遞到其基本（ Class1 ）構造函數中。 那可能嗎？

更完整的代碼：

class Base   
{  
    public Base() {  
        Console.WriteLine("Inside Base Constructor");  
    }
    ~Base() {  
        Console.WriteLine("Inside Base Destructor");  
    }  
}  

class Derived1: Base {  
    public Derived1() {  
        Console.WriteLine("Inside The Derived1 Constructor");  
    }
    ~Derived1() {  
        Console.WriteLine("Inside The Derived1 Destructor");  
    }  
}

class Derived2: Base {  
    public Derived2() {  
        Console.WriteLine("Inside The Derived2 Constructor");  
    }
    ~Derived2() {  
        Console.WriteLine("Inside The Derived2 Destructor");  
    }  
}

class Class1  
{  
    protected int a, b;  
    public Class1() {  
        a = 0;  
        b = 0;  
        Derived1 obj=new Derived1();
        Console.WriteLine("Inside base class default constructor");  
    }  
    public Class1(int a, int b, Derived1) {  
        this.a = a;  
        this.b = b;  
        Derived1 obj=new Derived1();
        Console.WriteLine("Inside base class parameterized constructor");  
    }  
}  
class Class2: Class1 {  
    int c;  
    public Class2(int a, int b, int c): base(a, b, Derived1) {  
        this.c = c;  
        Console.WriteLine("Inside derived class parametrized constructor");  
    }  
}  

即，通過base(a, b, Derived1)我想從Class2構造函數/定義傳遞Derived1 ，無論Class1是Derived1還是Derived2 ，它將是哪種類型的新類型。

希望我做了這個 盤繞 /復雜的問題明確。

Answer 1

您還可以使用下面使用的typeof關鍵字：

class Class2 : Class1
{
    int c;
    public Class2(int a, int b, int c) : base(a, b, typeof(Derived1))
    {
        this.c = c;
        Console.WriteLine("Inside derived class parametrized constructor");
    }
}

void Main()
{
    Class2 c2 = new Class2(1,2, 3);
}

或者使用如下C＃泛型編寫更通用的形式：

class Class1<T> where T: new()
{
    protected int a, b;
    public Class1()
    {
        a = 0;
        b = 0;
        T obj = new T();
        Console.WriteLine("Inside base class parameterized constructor, with {0}", typeof (T));
    }

    public Class1(int a, int b)
    {
        this.a = a;
        this.b = b;
        T obj = new T();
        Console.WriteLine("Inside base class parameterized constructor");
    }
}

class Class2<T> : Class1<T> where T: new()
{
    int c;
    public Class2(int a, int b, int c) : base(a, b)
    {
        this.c = c;
        Console.WriteLine("Inside derived class parametrized constructor");
    }
}


void Main()
{
    var c2 = new Class2<Derived1>(1, 2, 3);
    Console.WriteLine("-----");
    var c2_2 = new Class2<Derived2>(1, 2, 3);
}

輸出將是：

Inside Base Constructor
Inside The Derived1 Constructor
Inside base class parameterized constructor, with Derived1
Inside derived class parametrized constructor
-----
Inside Base Constructor
Inside The Derived2 Constructor
Inside base class parameterized constructor, with Derived2
Inside derived class parametrized constructor

希望對您有所幫助。