在C＃中访问数据结构中通用类型对象的通用方法

Question

I am trying to have a datastructure of an abstract class so I can access a method of different objects implementing that abstract class. This is my code:

    using Subsync.App;
    List<App> installed_apps = new List<object>();
    public Views (string[] args)
            {
                //INSTALL APPS HERE.
                installed_apps.Add (new HelloWorld.HelloWorld ());
                //INSTALL END

                foreach (App app in installed_apps) {
                    foreach (KeyValuePair<string, List<object>> match in app.getTokens ()) {
                        tokens.Add (match.Key, match.Value);
                    }
                }

                //begin dispatch
                Dictionary<string,List<object>> tokenized = Tokenize(args);
                Dispatch(tokenized);
            }

In namespace Subsync:

public abstract class App
    {
        public abstract Dictionary<string, List<object>> getTokens ();
    }

In namespace HelloWorld:

public class HelloWorld : App
{

    public HelloWorld ()
    {
    }

    public override Dictionary<string, List<object>> getTokens ()
    {
        Dictionary<string, List<object>> ret = new Dictionary<string, List<object>> ();
        ret.Add("helloworld",new List<object>() {"0","-hw","-helloworld"});
        return ret;
    }
}

Compiling gives me the error

Error CS0246: The type or namespace name `App' could not be found. Are you missing a using directive or an assembly reference? (CS0246) (App)

All the code files are in the same project folder. What am I doing wrong? Thanks!

Answer 1

将摘要作为头等修饰符，而不是公共。