using LINQ inside a function ..

Question

 public List<NDT_Equipment> GetALLRecords()
    {
        using (NDT_DB)
        {
            return (from a in NDT_DB.NDTEquipment select a);
        }
    }

• where : NDT_DB - class instance of the autogenerated database context class NDT_Equipment - partial class inside the database context class

• what I want :

  • return all records from table NDTEquipment
• what Im getting : " are you missing a cast " error everytime I compile ..

question : - am I allowed to use the NDT_Equipment partial class as a return value to be used in my VIEWMODEL ??? or I need to create a specific class to contain the results from this LINQ statement and that class is to be used in my VIEWMODEL ?

Answer 1

Try this:

return (from a in NDT_DB.NDTEquipment select a).ToList();

Answer 2

I think you're getting the error because the LINQ statement doesn't return a List (which your method signature states). Try changing this line:

return (from a in NDT_DB.NDTEquipment select a);

To:

return (from a in NDT_DB.NDTEquipment select a).ToList();

Answer 3

The LINQ query is returning an IQueryable, not a list, so you need to convert it to a list first:

return (from a in NDT_DB.NDTEquipment select a).ToList();

Answer 4

If you don't really need to use the features provided by List<NDT_Equipment> I would change the signature of the method to return IEnumerable<NDT_Equipment> instead:

public IEnumerable<NDT_Equipment> GetALLRecords()
{
    using (NDT_DB)
    {
        return (from a in NDT_DB.NDTEquipment select a);
    }
}

Update
There seems to be something strange in the code though; the generic type argument in the method is NDT_Equipment while the data entity is called NDTEquipment; are you specifying the correct type argument? If you point at a in your code, what type is it reported to be? That is the type you should have in the generic type argument.