Question

I have a datacontext, and it has Authors table.

public partial Author:IProductTag{}

I want to cast Table<Authors> object to Table<IProductTag>, but that appears to be impossible. I am trying to do that because I want my method to be able to work with different tables which come as input parameters. To be more specific, I need to execute OrderBy and Select methods of the table. I have few other tables, entities of which implement IProductTag . Also, I tried to write a function like:

public static void MyF<t>(){ 
Table<t> t0 = (Table<t>)DataContext.GetMyTableUsingReflection(); 
}

But it fails at compile-time. And if I cast the table to something like ITable or IQueriable, then the OrderBy and Select functions simply don’t work. So how do you deal with it?

Answer 1

I suspect you want to make your method generic – so instead of

void DoSomethingWithTable(Table<IProductTag> table)

you should have

void DoSomethingWithTable<T>(Table<T> table) where T : class, IProductTag

That should work fine, assuming you only need to read entities (and apply query operators etc). If that doesn’t work for you, please give more details about what your method needs to do.

(You say that your attempt to use reflection failed, but you haven’t said in what way it failed. Could you give more details?)