Question

I am getting the ID of an entry in a database table in my codebehind, and am trying to find a simple LINQ query to delete the entry based on the ID.

Here is what I have:

DataContext.Items.DeleteObject((Item)DataContext.Items.Where(item => item.ItemId == selectedId));

This gives me a casting error however, and I am wondering if there is a better way to accomplish this? I’ve looked at similar questions and every answer I see seems to be more complicated than this should actually be, so any suggestions would be great!

Answer 1

You currently have an IQueryable<Item>, not and Item – use Single() to get the item itself:

var item = DataContext.Items.Where(item => item.ItemId == selectedId).Single();
DataContext.Items.DeleteObject(item);

This assumes a single matching item (ID as primary key), otherwise consider using First() of FirstOrDefault() with a null check instead or if you have a collection of item, just delete them in a loop:

var items = DataContext.Items.Where(item => item.ItemId == selectedId);
foreach(var item in items)
  DataContext.Items.DeleteObject(item);