抽象类>子类的强制构造函数 [英] Abstract class > mandatory constructor for child classes

问题描述

可能重复:
为什么我不能创建

我如何编写一个抽象类来告诉子类必须具有一个构造函数?

How can I write one abstract class that tells that is mandatory for the child class to have one constructor?

类似这样的东西:

public abstract class FatherClass
{

    public **<ChildConstructor>**(string val1, string val2)
    {

    }

   // Someother code....
}

public class ChildClass1: FatherClass
{
    public ChildClass1(string val1, string val2)
    {
       // DO Something.....
    }
}

更新1:

如果我不能继承构造函数.如何防止某人不会忘记实现特定的子类构造函数????

UPDATE 1:

If I can't inherit constructors. How can I prevent that someone will NOT FORGET to implement that specific child class constructor ????

推荐答案

您不能.

但是，您可以像这样在FatherClass上设置单个构造函数:

However, you could set a single constructor on the FatherClass like so:

protected FatherClass(string val1, string val2) {}

哪个会强制子类调用此构造函数-这会鼓励"它们提供 string val1，string val2 构造函数，但不强制执行.

Which forces subclasses to call this constructor - this would 'encourage' them to provide a string val1, string val2 constructor, but does not mandate it.

我认为您应该考虑使用抽象工厂模式.看起来像这样:

I think you should consider looking at the abstract factory pattern instead. This would look like this:

interface IFooFactory {
    FatherClass Create(string val1, string val2);
}

class ChildClassFactory : IFooFactory
{
    public FatherClass Create(string val1, string val2) {
        return new ChildClass(val1, val2);
    }
}

无论何时需要创建FatherClass子类的实例，都可以使用IFooFactory而不是直接构造.这使您能够强制使用(字符串val1，字符串val2)签名来创建它们.

Wherever you need to create an instance of a subclass of FatherClass, you use an IFooFactory rather than constructing directly. This enables you to mandate that (string val1, string val2) signature for creating them.

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