我如何使这个ImageList类通用,以便它可以使用任何资源？

Question

对于我的游戏,我正在创建一个资源类,管理器资源喜欢纹理,声音,字体等.我制作了这个ImageList类,它在运行时根据需要自动加载纹理.

class TextureList
{
    private Dictionary<string, Texture> _list;

    public Texture this[string name]
    {
        get
        {
            Texture tex;
            bool success = List.TryGetValue(name, out tex);

            if (!success)
            {
                tex = Resources.LoadImage(name);
                List[name] = tex;
            }

            return tex;
        }
    }

    protected Dictionary<String, Texture> List
    {
        get
        {
            return _list ?? new Dictionary<String, Texture>();
        }
    }
}

现在我想使这个类变得通用,这样我就可以创建一个FontList或SoundList类,而无需将每个纹理更改为Sound或Font(以及编写大量重复代码).有谁愿意帮我制作这个的通用版本？

Answer 1

1. 让你的班级通用
2. 在构造函数中,您必须传递一个Func,其中T是您的泛型参数.
3. 逻辑如下:当您找不到该项时,将调用传入的Func并将结果存储在内部列表中.

所以,你的班级变成了

var x = new Cachinglist<Texture>(s => Resources.LoadImage(s));

要么

class CachingList<T>
{
    private readonly Dictionary<string, T> _list = new Blabla..();
    private readonly Func<string,T> _itemsFactory;

    public CachingList(Func<string,T> itemsFactory) {
      _itemsFactory = itemsFactory;
    }

    public T this[string name]
    {
        get
        {
            T t;

            if (!_list.TryGetValue(name, out t))
            {
                t = _itemsFactory(name);
                _list[name] = t;
            }

            return t;
        }
    }
}

Answer 2

假设你的纹理,声音等都有一个共同的基类(我将在BaseResource本例中调用它),创建一个具有加载器的通用基类.

public abstract class ResourceList<TYPE> where TYPE : BaseResource // change to your actual base-class or interface
{
    private Dictionary<string, TYPE> resources_ = new Dictionary<string, TYPE>();

    // loader
    protected abstract TYPE LoadImpl(string name);

    public TYPE this[string name]
    {
        get
        {
            TYPE resource;
            if(!resources_.ContainsKey(name))
            {
                resource = LoadImpl();
                resources_[name] = resource;
            }
            else
                resource = resources_[name];

            return resource;
        }
    }
} // eo class ResourceList

现在,为不同的资源提供具体的实现:

public class TextureList : ResourceList<Texture>
{
    protected override Texture LoadImpl(string name)
    {
        return Resources.LoadImage(name);
    }
}

也许你的声音看起来像这样:

public class SoundList : ResourceList<Sound>
{
    protected override Sound LoadImpl(string name)
    {
         return Resources.LoadSound(name);
    }
}