C# 基本构造函数确定

Question

我可以根据 C# 中的一些非实例相关条件来选择基构造函数吗？如果我不能，有什么想法可以满足我的要求吗？谢谢！

class X {}

class Y {}

class A {
    public A(X x) {}
    public A(Y y) {}
    // I don't want to add another constructor with an optional argument
}

class B : A {
    private static y = new Y();
    // I want to call different base constructor based on the value of argument `x`
    public B(X x=null) : base(x!=null? (X)x: (Y)y) {} // x, y here doesn't related to any instance
}

Answer 1

听起来你在找 Factory method:

https://refactoring.guru/design-patterns/factory-method/csharp/example

Factory method is a creational design pattern which solves the problem of creating product objects without specifying their concrete classes.

Factory Method defines a method, which should be used for creating objects instead of direct constructor call (new operator). Subclasses can override this method to change the class of objects that will be created.

这是一个很好的 C# 示例：

Factory Method Design Pattern In C#

C# 基本构造函数确定

C# base constructor determination

c#