Question

我有哪些解决以下并行继承层次结构问题的选项？我想让Serializer类保持无状态。

public abstract class BaseSerializerOptions
{
    public Boolean SortComponents { get; set; }
}

public class TextSerializerOptions : BaseSerializerOptions
{
    public Int32 TrimStrings { get; set; }
}

public class BinarySerializerOptions : BaseSerializerOptions
{
    public Boolean SkipNulls { get; set; }
}

public abstract class BaseSerializer
{
    public abstract void Serialize(Object obj, Stream s, BaseSerializerOptions opt);
}

public class TextSerializer : BaseSerializer
{
    public override void Serialize(Object obj, Stream s, TextSerializerOptions opt)
    {
    }
}

public class BinarySerializer : BaseSerializer
{
    public override void Serialize(Object obj, Stream s, BinarySerializerOptions opt)
    {
    }
}

我希望能够编写如下方法：

    static void Test(BaseSerializer s, BaseSerializerOptions o)
    {
        var obj = new MyObject { ... };
        using (var f = File.OpenWrite("..."))
        {
            s.Serialize(obj, f, o);
        }
        // do more things here to check the serializer result; 
        // the serializers might return some kind of operation status, which I want to check
    }

    static void TestSerializers()
    {
        Test(new TextSerializer(), new TextSerializerOptions {...});
        Test(new BinarySerializer(), new BinarySerializerOptions {...});
    }

Answer 1

扩大评论中的第一个建议：

public abstract class BaseSerializerOptions
{
    public Boolean SortComponents { get; set; }
}

public class TextSerializerOptions : BaseSerializerOptions
{
    public Int32 TrimStrings { get; set; }
}

public class BinarySerializerOptions : BaseSerializerOptions
{
    public Boolean SkipNulls { get; set; }
}

public abstract class BaseSerializer<T> where T : BaseSerializerOptions
{
    public abstract void Serialize(Object obj, Stream s, T opt);
}

public class TextSerializer : BaseSerializer<TextSerializerOptions>
{
    public override void Serialize(Object obj, Stream s, TextSerializerOptions opt)
    {
    }
}

public class BinarySerializer : BaseSerializer<BinarySerializerOptions>
{
    public override void Serialize(Object obj, Stream s, BinarySerializerOptions opt)
    {
    }
}

更新特定语法用法：

public class TextSerializer : BaseSerializer
{
    public void Serialize(Object obj, Stream s, TextSerializerOptions opt)
    {
        this.Serialize(obj, s, opt);
    }

    public override void Serialize(object obj, Stream s, BaseSerializerOptions opt)
    {
        if (opt is TextSerializerOptions options)
        {

        }
        else
        {

        }
    }
}

public class BinarySerializer : BaseSerializer
{
    public void Serialize(Object obj, Stream s, BinarySerializerOptions opt)
    {
        this.Serialize(obj, s, opt);
    }

    public override void Serialize(object obj, Stream s, BaseSerializerOptions opt)
    {
        if (opt is BinarySerializerOptions options)
        {

        }
        else
        {

        }
    }
}

Answer 2

几年前，我有机会使用Haskell学习了一些有关函数式编程的知识，而大多数FP概念对我来说似乎都很直观。由于我对问题的建议不满意，所以我有一个很好的主意要问自己：我将如何在Haskell中做到这一点？因此，下面是我从FP角度进行思考而得出的解决方案。基本上，我放弃一种继承层次结构（带有序列化程序类的那些），而改用静态方法。函数式编程使我成为一个更好的OOP程序员...真实的故事！

public abstract class BaseSerializerOptions
{
    Boolean SortComponents { get; set; }
}

public class TextSerializerOptions : BaseSerializerOptions
{
    public Boolean TrimStrings { get; set; }
}

public class BinarySerializerOptions : BaseSerializerOptions
{
    public Boolean SkipNulls { get; set; }
}

public class SerializerResult
{

}

public static class Serializer
{
    public static SerializerResult Write(Object obj, Stream s, BaseSerializerOptions opt)
    {
        switch (opt)
        {
            case TextSerializerOptions o: return WriteText(obj, s, o);
            case BinarySerializerOptions o: return WriteBinary(obj, s, o);
        }
        throw new Exception();
    }

    public static SerializerResult WriteText(Object obj, Stream s, TextSerializerOptions opt)
    {
        return null;
    }

    public static SerializerResult WriteBinary(Object obj, Stream s, BinarySerializerOptions opt)
    {
        return null;
    }
}

class Program
{
    static void Test(BaseSerializerOptions o)
    {
        var obj = new Object();

        using (var fs = File.Open("...", FileMode.Create))
        {
            var r1 = Serializer.Write(obj, fs, o);
            CheckSerializerResults(r1);
        }
    }

    static void TestSerializers()
    {
        Test(new TextSerializerOptions { TrimStrings = true });
        Test(new BinarySerializerOptions { SkipNulls = false });
    }

    static void CheckSerializerResults(SerializerResult r)
    {

    }
}

覆盖并行类层次结构中的方法

2 个答案: