Link to home
Start Free TrialLog in
Avatar of MobileAccess
MobileAccessFlag for Belgium

asked on

Problem with converting variable to Generic class

I' trying to achieve the following :
I have an interface with an method in it :

---------------------------------------------------------------------
  public interface IDetailPaneUserControl<T>
  {
    T SelectedItem { get; set; }

    Task LoadView(RadPane paneContainer, T item, PaneUserControl parentPane = null);

    Task LoadView(RadPane paneContainer, Guid? id, PaneUserControl parentPane = null);
  }
---------------------------------------------------------------------

The Implementation is like the following :

---------------------------------------------------------------------
 public class DetailPaneUserControl<T> : PaneUserControl, IDetailPaneUserControl<T>, IMayBeClosed where T : class, IBaseEntity, new()
---------------------------------------------------------------------

This class is inherited in my usercontrol.

However I now need to check of a control is of this type and use a method of it. I cannot give with type, but it have to have the IBaseEntity interface.

---------------------------------------------------------------------
 if (item != null)
            {
                var itemType = item.GetType();
                if (paneContent is IDetailPaneUserControl<itemType>)
                    await ((IDetailPaneUserControl<itemType>) paneContent).LoadView(pane, item);
            }
---------------------------------------------------------------------

The item.GetType() isn't working, saying that itemType is a variable but used as an type.

Any idea's how to get the code working?
Avatar of AndyAinscow
AndyAinscow
Flag of Switzerland image

Does changing
var itemType = item.GetType();
to
Type itemType = item.GetType();
cure it?
My guess is that this line:

if (paneContent is IDetailPaneUserControl<itemType>)

is expecting an actual Type in <itemType> and what you're passing in is looked upon as a variable.

If AndyAinscow's solution doesn't fix it, I might try something like:

if (paneContent is IDetailPaneUserControl<Item>)

Open in new window


where
Item 

Open in new window

is the true class name of the itemType object. I don't see that in your code.
Avatar of MobileAccess

ASKER

The problem is that I cannot code it like that. It needs to be specified at runtime. So I can't place the real name (type) of the item. it needs to be dynamic
Do you mean my suggestion doesn't compile and/or run  ?
I think he means mine, because he can't determine the type until run-time.

I'm thinking of using the Dynamic keyword here, but I don't have an example off hand.  It's just a thought and might not really be correct.
It would be nice for the asker to respond so we know which isn't working.  Or close the question if one does actually solve it.
Just guessing is going to waste everyones time.
Andy, I'm sorry, I was sick last week...
Your method I've tried, but the problem stays the same.

Daniel,
Indeed, I do not know the type accept at runtime. I'll take a look at the dynamic approach, haven't used this before...
Apparently, this is doable.

This builds. Not promising you it will run!

        Item item = new Item();
        PaneUserControl paneContent = new PaneUserControl();
        RadPane pane = new RadPane();

        if (item != null)
        {
            var genericItemType = item.GetType();
            var specificItemType = genericItemType.MakeGenericType(item.GetType());
            var list = Activator.CreateInstance(specificItemType);
            if (paneContent is IDetailPaneUserControl<Item>)
            {
                ((IDetailPaneUserControl<Item>)paneContent).LoadView(pane, item);
            }
        }

Open in new window

Ugh. I made a mistake. Let me fix it. That does not answer your question.
ASKER CERTIFIED SOLUTION
Avatar of Daniel Van Der Werken
Daniel Van Der Werken
Flag of United States of America image

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
Thanks, I'll try this tomorrow :)