实体框架5 Remove（）不能从数据库中删除

Question

I have a User object and when it is deleted using Remove() on the DbContext, it is not being deleted from the Database. Strangely enough, my queries for retrieving Users no longer return it though.

This code is used through my application and works for other entities without any problems.

I'd really appreciate suggestions as to what this could be, as I'm stumped!

#region Delete
    public virtual void Delete(User entity)
    {
        var user = _context.Users.FirstOrDefault(u => u.UserId == entity.UserId);
        if (user != null)
        {
            user.Roles.Clear();
            var actionHistories = _context.ActionHistories.Where(u => u.User.UserId == user.UserId);
            foreach (var actionHistory in actionHistories)
            {
                _context.ActionHistories.Remove(actionHistory);
            }
            _context.Users.Remove(user);

            _context.SaveChanges();
        }
    }
    #endregion

PS The code for removing Roles and ActionHistories was added by me to test if the problem was with related entities existing, but it did not fix the problem.

Answer 1

Try adding:

_context.Entry(user).State = EntityState.Modified;

before

_context.SaveChanges();

Answer 2

I used the same answer as @tomsullivan1989 but with EntityState.Deleted; and it solved my similar problem. Which had error message The relationship could not be changed because one or more of the foreign-key properties is non-nullable

Answer 3

My suggestion would be to try using a profiling tool (eg EFprof from hibernating rhino's, which has a free trial).

It will show you exactly what SQL EF generated, so you can watch what happens as you step past SaveChanges.

It does sound odd, perhaps there's some silent SQL error that's being thrown that a profiler may reveal.

Answer 4

The Problem is the "Virtual" _context you must delete in main Context in this Case Like this

Database.Context.Remove<ActionHistories>(actionHistory); 

Then save Changes in Main Context

Database.Context.SaveChanges();