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How to delete an object by id with entity framework

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How do I use RemoveRange in Entity Framework?

RemoveRange() method attaches a collection of entities with Deleted state, which in turn will execute the DELETE command for all entities on SaveChanges() . Adding or removing entities using the AddRange and RemoveRange methods improves the performance.

How do I remove a navigation property in Entity Framework?

. Clear() method is very good. It deletes all navigation properties in database. That's simple rather than foreach loop.


In Entity Framework 6 the delete action is Remove. Here is an example

Customer customer = new Customer () { Id = id };
context.Customers.Attach(customer);
context.Customers.Remove(customer);
context.SaveChanges();

The same as @Nix with a small change to be strongly typed:

If you don't want to query for it just create an entity, and then delete it.

Customer customer = new Customer () { Id = id };
context.Customers.Attach(customer);
context.Customers.DeleteObject(customer);
context.SaveChanges();

Similar question here.

With Entity Framework there is EntityFramework-Plus (extensions library).
Available on NuGet. Then you can write something like:

// DELETE all users which has been inactive for 2 years
ctx.Users.Where(x => x.LastLoginDate < DateTime.Now.AddYears(-2))
     .Delete();

It is also useful for bulk deletes.


If you dont want to query for it just create an entity, and then delete it.

Customer customer  = new Customer() {  Id = 1   } ; 
context.AttachTo("Customers", customer);
context.DeleteObject(customer);
context.Savechanges();

I am using the following code in one of my projects:

    using (var _context = new DBContext(new DbContextOptions<DBContext>()))
    {
        try
        {
            _context.MyItems.Remove(new MyItem() { MyItemId = id });
            await _context.SaveChangesAsync();
        }
        catch (Exception ex)
        {
            if (!_context.MyItems.Any(i => i.MyItemId == id))
            {
                return NotFound();
            }
            else
            {
                throw ex;
            }
        }
    }

This way, it will query the database twice only if an exception occurs when trying to remove the item with the specified ID. Then if the item is not found, it returns a meaningful message; otherwise, it just throws the exception back (you can handle this in a way more fit to your case using different catch blocks for different exception types, add more custom checks using if blocks etc.).

[I am using this code in a MVC .Net Core/.Net Core project with Entity Framework Core.]


This answer is actually taken from Scott Allen's course titled ASP.NET MVC 5 Fundamentals. I thought I'd share because I think it is slightly simpler and more intuitive than any of the answers here already. Also note according to Scott Allen and other trainings I've done, find method is an optimized way to retrieve a resource from database that can use caching if it already has been retrieved. In this code, collection refers to a DBSet of objects. Object can be any generic object type.

        var object = context.collection.Find(id);  
        context.collection.Remove(object);
        context.SaveChanges();