泛型函数的静态方法调用

Question

Is it possible to make a call to static method from generic function?

I need to do something like this:

public static T CreateNewProject<T, V>(string token, string projectName)
     where V : IProject<T>
{
   V.LoadProject();
}

where LoadProject() MUST be some static method of some class.

Answer 1

You can't do that with constraints, but you can use Reflection . It looks like the only choice in this case:

typeof(V).GetMethod("LoadProject", BindingFlags.Static | BindingFlags.Public)
         .Invoke(null);

Answer 2

What you could do is instead of using static classes is use a singleton:

public interface ICanLoadProject
{
    void LoadProject(string token, string projectName);
}

Implementation:

public class SampleProjectLoader : ICanLoadProject
{
    private static SampleProjectLoader instance = new SampleProjectLoader();

    private SampleProjectLoader(){} 

    public static SampleProjectLoader Instance { get{ return instance; } }

    public void LoadProject(string token, string projectName)
    { /*Your implementation*/ }

}

then the generic works with:

where V : ICanLoadProject

all you have to do with the code accessing the Method before is:

SampleProjectLoader.Instance.LoadProject("token","someName");

the method could be:

public static class ExtensionMethods
{
    public static T CreateNewProject<T, V>(this V loader, string token, string projectName) where V : ICanLoadProject
    {
        loader.LoadProject(token, projectName);
        return default(T); //no clue what you want to return here
    }
}

And will be called like:

static void Main(string[] args)
{
    object result = SampleProjectLoader.Instance.CreateNewProject<object, SampleProjectLoader>("token", "someName");
}

Or better yet:

public static class ExtensionMethods
{
    public static T CreateNewProject<T>(this ICanLoadProject loader, string token, string projectName)
    {
        loader.LoadProject(token, projectName);
        return default(T); //no clue what you want to return here
    }
}

and call with:

SampleProjectLoader.Instance.CreateNewProject<object>("token", "someName");