动态创建一个泛型类型，该类型使用类型本身作为泛型参数

Question

Here a dummy code to explain my problem:

public class A<TX, TA> where TA : A<TX, TA>
{

}

public void Do()
{
   var doy = typeof(A<,>).MakeGenericType(typeof(string), null/*??????*/));
}

How can I make a type from my generic type, if I can't identifty my type to use it as parameter?

Thanks for your help.

Edit, example of doing it statically:

public abstract class A<TX, TA> where TA : A<TX, TA>
{
    public TA ChainMethod()
    {
        return (TA)this;
    }
}

public class AConcrete : A<string, AConcrete>
{
    public AConcrete OtherMethod()
    {
    return this;
    }
}

public class App
{
    public static void Start()
    {
    new AConcrete().ChainMethod().ChainMethod().OtherMethod();
    }
}

Answer 1

You need to design your class hierarchy. It seems like it's not quite there yet. Please check out this example, hope it will give you an idea:

abstract class BaseBuilder<TBrick>
{
    public BaseBuilder<TBrick> AddBrick(TBrick brick)
    {
        // ...
        return this;
    }
}

class Builder : BaseBuilder<ConcreteBrick>
{
    public Builder AddRoof()
    {
        // ...
        return this;
    }

    public new Builder AddBrick(ConcreteBrick brick) 
    {
        base.AddBrick(brick);
        return this;
    }
}

And it will look like this:

new Builder()
    .AddBrick(new ConcreteBrick())
    .AddBrick(new ConcreteBrick())
    .AddRoof();

I think you won't be able to chain calls with inheritance if you don't override methods with new keyword like I suggested. Though you can implement things easily if you give up an idea of chaining calls.