DynamicObject. How execute function through TryInvoke?

Question

I want to execute static functions through DynamicObject, but I don't know how execute saveOperation without specifying the class name typeof(Test1) or typeof(Test2) . How relise this better?

For example

class DynObj : DynamicObject
{
    GetMemberBinder saveOperation;
    public override bool TryGetMember(GetMemberBinder binder, out object result)
    {
        saveOperation = binder;
        result = this;
        return true;
    }

    public override bool TryInvoke(InvokeBinder binder, object[] args, out object result)
    {
        Type myType = typeof(Test1 or Test2 or ....);

        result = myType.GetMethod(saveOperation.Name).Invoke(null, args);
        return true;
    }
 }
 class Program
    {
        static void Main(string[] args)
        {
            dynamic d1 = new DynObj();
            d1.func1(3,6);
            d1.func2(3,6);
        }
  }

 class Test1
 {
    public static void func1(int a, int b){...}
 }

 class Test2
 {
    public static void func2(int a, int b){ ...}
 }

Second way defines static function with attribute ( offered by Carnifex )

 class Test3
 {
    [DynFuncMemberAttribute] 
    public static void func3(int a, int b){...}
 }

and get type

     public override bool TryInvoke(InvokeBinder binder, object[] args, out object result)
    {
        Type myType = null;
        foreach (Type types in Assembly.GetExecutingAssembly().GetTypes())
        {
            foreach (MethodInfo mi in types.GetMethods())
            {
                foreach (CustomAttributeData cad in mi.CustomAttributes)
                {
                    if (cad.AttributeType == typeof(DynFuncMemberAttribute))
                    {
                        myType = types;
                        break;
                    }
                }
            }
        }

        result = (myType != null)? myType.GetMethod(saveOperation.Name).Invoke(null, args): null;
        return myType != null;
    }

Answer 1

You could use some Attributes and set eg. [DynFuncMemberAttribute] to the class or to the method it self.

Then inside TryInvoke (or constructor) get all types/methods marked with this attribute, build some map/cache and voila :)

---

Edit: this is example of use this attribute. Remember that BuildCache() will throw exception if two method with the same name will be found.

[AttributeUsage(AttributeTargets.Method)]
class DynFuncMemberAttribute : Attribute
{
}

class DynObj : DynamicObject
{
    Dictionary<string, MethodInfo> cache;
    GetMemberBinder saveOperation;
    public override bool TryGetMember(GetMemberBinder binder, out object result)
    {
        saveOperation = binder;
        result = this;
        return true;
    }

    public override bool TryInvoke(InvokeBinder binder, object[] args, out object result)
    {
        if (cache == null)
            cache = BuildCache();

        MethodInfo mi;
        if (cache.TryGetValue(saveOperation.Name, out mi))
        {
            result = mi.Invoke(null, args);
            return true;
        }

        result = null;
        return false;
    }

    private Dictionary<string, MethodInfo> BuildCache()
    {
        return Assembly.GetEntryAssembly()
            .GetTypes()
            .SelectMany(t => t.GetMethods(BindingFlags.Public | BindingFlags.Static))
            .Where(mi => mi.GetCustomAttribute<DynFuncMemberAttribute>() != null)
            .ToDictionary(mi => mi.Name);
    }
}

class Program
{
    static void Main(string[] args)
    {
        dynamic d1 = new DynObj();
        d1.func1(3, 6);
        d1.func2(3, 6);
    }
}

class Test1
{
    [DynFuncMember]
    public static void func1(int a, int b)
    {
        Console.WriteLine("func1");
    }
}

class Test2
{
    [DynFuncMember]
    public static void func2(int a, int b)
    {
        Console.WriteLine("func2");
    }
}