Converting String -> Type for uses with generics

Question

Im trying to pass Type and reference to a generic via a string of the same name:

IE: string ButtonName == "ActionOne" ~~~~~>> Type == ActionOne, reference == ActionOne

Sadly I have no idea what the right syntax for this is, and am having a hard time finding it via google, so if someone knows how to do this, or at-least what it is called, it would help a huge amount!!

Thanks, and here is some sudo code of what i'm trying to do!

public class ActionPanelButton : *NotImportant* {
    private string ButtonName;
    private Type ButtonType; 

    void ActionPanelButton(){
            ButtonName = this.Button.name; // This is return a string set by the user
            ButtonType = Type.GetType(ButtonName);
            ActionPanel = this.Button.parent.ActionPanel;  //  This will return the containing panel object 
    }   

    public void LeftClick(){ //This responds like any-ol OnClick

        ActionPanel.ChangeSelectedActionBundle<(ButtonType)>(ActionPanel.DisplayedActionPanel.(ButtonType));
    }
}

public class ActionPanel....

public void ChangeSelectedActionBundle <T> (T action){

        Type typeOfObject = typeof(ActionBundle);
        Type typeOfAction = typeof(T);

        FieldInfo field = typeOfObject.GetField(typeOfAction.Name);
        field.SetValue(SelectionManager.SelectedActionBundle, action);
    }

Since generics work through the compiler, the type needs to be known at compile time. There's not really an easy way to do what you're doing, short of using reflection. — Mike Christensen
– Mike Christensen, Commented Sep 24, 2013 at 22:20
I'm having a hard time understanding what you're after. Can you perhaps change the example? It does appear though that Reflection is more what you're after.. not generics. — Simon Whitehead
– Simon Whitehead, Commented Sep 24, 2013 at 22:20
As soon as I get home, I will expand my context!! Thanks for trying to help! — Burdock
– Burdock, Commented Sep 24, 2013 at 22:23
@Burdock - They want to call a generic method based on a type that's only known at runtime. — Mike Christensen
– Mike Christensen, Commented Sep 24, 2013 at 22:24
@MikeChristensen has it right~ Let me check my code and I will update the post... — Burdock
– Burdock, Commented Sep 24, 2013 at 22:37

Mike Christensen · Accepted Answer · 2013-09-24 22:56:03Z

Generic functions are actually more a compiler feature than a runtime feature. When the compiler runs into code such as:

myObj.Foo<Int32>(123);

It will create an implementation of Foo using an Int32 instead of T. For this reason, you cannot call a generic function using a type that's only known as runtime.

However, I question why you need to do this. You're already using reflection in your ChangeSelectedActionBundle method. Nothing about it needs to be generic. You can just do:

public void ChangeSelectedActionBundle(object action)
{
   Type typeOfObject = typeof(ActionBundle);
   Type typeOfAction = action.GetType();

   FieldInfo field = typeOfObject.GetField(typeOfAction.Name);
   field.SetValue(SelectionManager.SelectedActionBundle, action);
}

Perhaps rather than using object, you could use a base class common to all your actions, use or an interface.

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