Question

I know that virtual and static methods are opposing concepts, but I think that it could make sense sometimes to use them together. There have been quite a bunch of similiar question on SO on this topic, but the following scenario has not been covered yet.

There’s a C# interface that looks like this:

interface IVertexMeshLoader
{
    VertexMesh LoadFromFile(string fname);
}

An implementation of that could look like this:

class VertexMeshLoaderObj : IVertexMeshLoader
{
    public VertexMesh LoadFromFile(string fname) { .. }
}

Now I would like to be able to call method without an object instance, but I cannot make the LoadFromFile() method static, because it implements the interface.

The best solution I worked out so far is to write a static method LoadFromFileStatic() that contains the actual code. The LoadFromFile() then just calls it. Not very pretty, imho.

I could also create an instance of VertexMeshLoadObj every time I want to call the method, but that is even worse.

Are there better ways? Thanks 🙂

Answer 1

Here’s another option. Provide an explicit implementation of the interface which just calls the static method. It allows them to have the same name

class VertexMeshLoaderObj : IVertexMeshLoader
{
  VertexMesh IVertexMeshLoader.LoadFromFile(string fname) { 
    LoadFromFile(fname);
  }
  public static VertexMesh LoadFromFile(fname) {
    ...
  }
}