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Microsoft Entity Framework is not saving changes

Im currently trying to implement CRUD functionality with a dbfactory and generics with microsoft EF, but while listing entries is working, making changes to the db is currently not working.
public class AbstractDataModel
{
[Key]
public Guid gid { get; set; }
}
Model
class SalesOrder : AbstractDataModel
{
public int salesOrderID { get; set; }
public int productID { get; set; }
public int customerID { get; set; }
public Guid createdBy { get; set; }
public string dateCreated { get; set; }
public string orderDate { get; set; }
public string orderStatus { get; set; }
public string dateModified { get; set; }
}
A DBCore with some other functionality besides the ones listed here, which are not relevant for the factory
public class DBCore : DbContext
{
public static string connectionString = "myConnectionStringToDb";
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
optionsBuilder.UseSqlServer(connectionString);
}
Data Service which calls factory
class SalesOrderService : DBCore
{
public DbSet<SalesOrder> SalesOrders { get; set; }
public OkObjectResult GetAllSalesOrders()
{
DBFactory factory = new DBFactory();
return new OkObjectResult(JsonConvert.SerializeObject(factory.GetAll(SalesOrders)));
}
public OkObjectResult AddSalesOrder(SalesOrder order)
{
order.gid = Guid.NewGuid();
return DBFactory.AddOne(order);
}
public OkObjectResult UpdateSalesOrder(SalesOrder order)
{
return DBFactory.UpdateOne(order);
}
public OkObjectResult DeleteSalesOrder(SalesOrder order)
{
return DBFactory.DeleteOne(order);
}
}
simple CRUD-Factory,
class DBFactory : DBCore
{
public DbSet<UserModel> Users { get; set; }
public DbSet<SalesOrder> SalesOrders { get; set; }
public List<T> GetAll<T>(DbSet<T> dbset) where T : class
{
using (this)
{
return dbset.ToList();
}
}
public static OkObjectResult AddOne<T>(T data)
{
using (DBFactory factory = new DBFactory())
{
factory.Add(data);
factory.SaveChanges();
return new OkObjectResult("Entry was sucessfully added");
}
}
public static OkObjectResult UpdateOne<T>(T data)
{
using (DBFactory factory = new DBFactory())
{
factory.Update(data);
factory.SaveChanges();
return new OkObjectResult("Entry was sucessfully updated");
}
}
public static OkObjectResult DeleteOne<T>(T data)
{
using (DBFactory factory = new DBFactory())
{
factory.Attach(data);
factory.Remove(data);
factory.SaveChanges();
return new OkObjectResult("Entry was sucessfully removed");
}
}
}
Edit: Following the advices i changed the code so it should SaveChanges for the Factory, which also contains the context as a property. But it still doesnt seem to work for all database operations except listing all entries
Editv2: Thanks for the adivces it seems i have solved that problem, but a new one appeared :D
I can now do database operations like deleting entries, but now i cant list the entries anymore because the following error occurs, although the code there didnt really change:
"Executed 'GetAllOrders' (Failed, Id=5fb95793-572a-4545-ac15-76dffaa7a0cf, Duration=74ms)
[2020-10-23T14:33:43.711] System.Private.CoreLib: Exception while executing function: GetAllOrders. Newtonsoft.Json: Self referencing loop detected for property 'Context' with type 'FicoTestApp.Models.SalesOrder'. Path '[0].ChangeTracker'."

try adding
services.AddControllers().AddNewtonsoftJson(x => x.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore);
to your
startup.cs
it should to the job

Populate a Razor view from two models

I am using entity framework in MVC. I have two models that populate from a SQL table using DBContext
public class Incident
{
public Guid IncidentKey { get; set; }
public int IncidentID { get; set; }
}
public class Request
{
public Guid RequestKey { get; set; }
public int RequestID { get; set; }
}
Below is how I am getting the the data to pull from SQL
public class CallViewerDbContext : DbContext
{
public DbSet<Incident> Incident { get; set; }
public DbSet<Request> Request { get; set; }
}
public class SqlData : IIncident, IRequest
{
private readonly CallViewerDbContext db;
public SqlData(CallViewerDbContext db)
{
this.db = db;
}}
internal static void RegisterContainer(HttpConfiguration httpConfiguration)
{
var builder = new ContainerBuilder();
builder.RegisterControllers(typeof(MvcApplication).Assembly);
builder.RegisterApiControllers(typeof(MvcApplication).Assembly);
builder.RegisterType<SqlData>()
.As<IIncident>()
.InstancePerRequest();
builder.RegisterType<SqlData>()
.As<IRequest>()
.InstancePerRequest();
builder.RegisterType<CallViewerDbContext>().InstancePerRequest();
var container = builder.Build();
DependencyResolver.SetResolver(new AutofacDependencyResolver(container));
httpConfiguration.DependencyResolver = new AutofacWebApiDependencyResolver(container);
}
I am trying to create a new model that will will allow me to get a count for both of the entity's when I put it on a new Razor view. I am currently able to get one by using the below method.
IIncident db;
public HomeController(IIncident db)
{
this.db = db;
}
public ActionResult Index()
{
var model = db.IGetAll();
return View(model);
}
public IEnumerable<Incident> IGetAll()
{
return db.Incident;
}
I have tried making a new model.
public class DataModel
{
public List<Incident> allIncidents { get; set; }
public List<Request> allRequests { get; set; }
}
I tried adding it to the Register Container
builder.RegisterType<SqlData>()
.As <IDataModel>()
.InstancePerRequest();
Then updated the Home controller
IDataModel db;
public HomeController(IDataModel db)
{
this.db = db;
}
public ActionResult Index()
{
var model = db.MGetAll();
return View(model);
}
public IEnumerable<Incident> MGetAll()
{
return db.Incident;
}
I am trying to return the data using the MGetAll method to get the list of Incidents, I then have a another method that does the same for requests. I was trying to return individual counts to the view first then add in the second.
I am now getting the below stack trace error
The model item passed into the dictionary is of type 'System.Data.Entity.DbSet1[CallViewerData.Models.Incident]', but this dictionary requires a model item of type 'System.Collections.Generic.IEnumerable1[CallViewerData.Models.DataModel]'.
Any help would be greatly appreciated.

Something like this should work:
public ActionResult Index()
{
var model = PrepareViewModel();
return View(model);
}
private DataModel PrepareViewModel()
{
return new DataModel
{
allIncidents = db..., // Get Incidents
allRequests = db... // Get Requests
};
}
And in your view
#model namespace.DataModel
Then you can access them with Model.allIncidents and Model.allRequests.

Entity Framework 6 - Dependency Injection with Unity - Repository pattern - Add or Update exception for many to many relationship

I have a problem when adding new values with a many to many mapping in Entity Framework. I know about the unit of work pattern but in our solution we would like to keep a simple repository pattern and not a unit of work class that contains everything. Is this possible or should I just implement Unit of Work right away?
If I don't use iSupplierRepository below a supplier will be added, but it will always add a new one even though there already exists one with that name.
Error:
The relationship between the two objects cannot be defined because
they are attached to different ObjectContext objects.
Repository example:
public class SupplierRepository : IntEntityRepository<Supplier, DbContext>, ISupplierRepository
{
public SupplierRepository(DbContext context) : base(context, context.Suppliers)
{
}
}
Inherited repositories:
public class IntEntityRepository<TEntity, TContext> : EntityRepository<TEntity, TContext, int>
where TEntity : class, IEntity<int>
where TContext : BaseIdentityDbContext
{
public IntEntityRepository(TContext context, IDbSet<TEntity> set) : base(context, set)
{
}
public override async Task<TEntity> GetAsync(int id)
{
return (await GetAsync(entity => entity.Id == id)).SingleOrDefault();
}
...
public abstract class EntityRepository<TEntity, TContext, TId> : IEntityRepository<TEntity, TId>
where TEntity : class, IEntity<TId>
where TContext : BaseIdentityDbContext
{
protected TContext Context { get; }
protected IDbSet<TEntity> Set { get; }
protected EntityRepository(TContext context, IDbSet<TEntity> set)
{
Context = context;
Set = set;
}
public abstract Task<TEntity> GetAsync(TId id);
...
Unity:
container.RegisterType<ISupplierRepository, SupplierRepository>();
container.RegisterType<IContactRepository, ContactRepository>();
Controller:
private readonly IContactRepository iContactRepository;
private readonly ISupplierRepository iSupplierRepository;
public ContactsController(IContactRepository iContactRepository, ISupplierRepository iSupplierRepository)
{
this.iContactRepository = iContactRepository;
this.iSupplierRepository = iSupplierRepository;
}
[HttpPut]
[Route("UpdateContact/{id}")]
public async Task<IHttpActionResult> UpdateContact(ContactViewModel contactVm, int id)
{
try
{
var supplierList = new List<Supplier>();
foreach (var contactVmSupplier in contactVm.Suppliers)
{
var supplier = await iSupplierRepository.GetAsync(contactVmSupplier.Id);
supplierList.Add(supplier);
}
var contactOriginal = await iContactRepository.GetAsync(id);
var updatedContact = Mapper.Map<ContactViewModel, Contact>(contactVm, contactOriginal);
updatedContact.Suppliers = supplierList;
await iContactRepository.UpdateAsync(updatedContact);
return Ok();
}
catch (Exception e)
{
throw new Exception("Could not update a contact", e);
}
}
Viewmodels:
public class ContactViewModel
{
public int Id { get; set; }
public string Name { get; set; }
public ICollection<SupplierViewModel> Suppliers { get; set; }
}
public class SupplierViewModel
{
public int Id { get; set; }
public string Name { get; set; }
}
Models:
public class Contact : IEntity<int>
{
public Contact()
{
Suppliers = new List<Supplier>();
}
[Key]
public int Id { get; set; }
public DateTime Created { get; set; }
public DateTime Updated { get; set; }
public string Name { get; set; }
public ICollection<Supplier> Suppliers { get; set; }
}
public class Supplier: IEntity<int>
{
public Supplier()
{
Contacts = new List<Contact>();
}
[Key]
public int Id { get; set; }
public DateTime Created { get; set; }
public DateTime Updated { get; set; }
public string Name { get; set; }
public virtual ICollection<Contact> Contacts { get; set; }
}

If you install the Unity bootstrapper for ASP.NET Web API package, a UnityHierarchicalDependencyResolver is available which will use a new child container for each IHttpController resolution effectively making all registrations with a HierarchicalLifetimeManager resolved per request so that all repository instances in a controller will use the same DbContext.
The NuGet package will also install some bootstrapping code in App_Start which uses WebActivatorEx. You can either use this approach or change to align with what you are using right now. Based on your posted code it would look something like:
public static void ConfigureUnity(HttpConfiguration config)
{
var container = new UnityContainer();
container.RegisterType<DbContext>(new HierarchicalLifetimeManager());
container.RegisterType<ISupplierRepository, SupplierRepository>();
container.RegisterType<IContactRepository, ContactRepository>();
config.DependencyResolver = new UnityHierarchicalDependencyResolver(container);
}

Solved it like this, dependency injection is from the tutorial Dependency Injection in ASP.NET Web API 2.
https://learn.microsoft.com/en-us/aspnet/web-api/overview/advanced/dependency-injection
App_Start -> WebApiConfig
public static void Register(HttpConfiguration config)
{
UnityConfig.ConfigureUnity(config);
...
UnityConfig:
public static void ConfigureUnity(HttpConfiguration config)
{
var context = new DbContext();
var container = new UnityContainer();
container.RegisterType<ISupplierRepository, SupplierRepository>(new InjectionConstructor(context));
container.RegisterType<IContactRepository, ContactRepository>(new InjectionConstructor(context));
config.DependencyResolver = new UnityResolver(container);
}

Update: Use Randy Levy's answer instead.
My recommendation here is not to use Repository or UoW at all. EF already has them implemented. You'll encounter a lot of issues trying to re-implement them.
As to specific issue you encounter with exception: you have to use the same DbContext for your entities. At the same time, you wouldn't like to use DbContext as Singleton and use it per-request instead. A possible solution for it might be found here.
Application_BeginRequest(...)
{
var childContainer = _container.CreateChildContainer();
HttpContext.Items["container"] = childContainer;
childContainer.RegisterType<ObjectContext, MyContext>
(new ContainerControlledLifetimeManager());
}
Application_EndRequest(...)
{
var container = HttpContext.Items["container"] as IUnityContainer
if(container != null)
container.Dispose();
}

Create database in App_Start

I have an solution with 2 projects, one domain class and one webUI.
In the domain class I have 2 models, a db context and a databas initializer.
List.cs:
namespace Todo.Domain
{
public class List
{
public int ListID { get; set; }
public string Day { get; set; }
public ICollection<Task> Tasks { get; set; }
}
}
Task.cs:
namespace Todo.Domain
{
public class Task
{
public int TaskID { get; set; }
public int ListID { get; set; }
public string TodoTask { get; set; }
}
}
EFDbContext.cs:
namespace Todo.Domain
{
public class EFDbContext : DbContext
{
public EFDbContext() : base("TodoList") { }
public DbSet<List> Lists { get; set; }
public DbSet<Task> Tasks { get; set; }
}
}
Initializer:
namespace Todo.Domain
{
public class TodoDbInit : System.Data.Entity.DropCreateDatabaseIfModelChanges<EFDbContext>
{
protected override void Seed(EFDbContext context)
{
var list = new List<List>
{
new List { Day="Måndag" }
};
list.ForEach(s => context.Lists.Add(s));
context.SaveChanges();
var task = new List<Task>
{
new Task { TodoTask="Fisk" }
};
task.ForEach(s => context.Tasks.Add(s));
context.SaveChanges();
}
}
}
Now, when I start my application, I want the database to be created. I have placed a setInitializer Global.asax:
namespace Todo.WebUI
{
public class MvcApplication : System.Web.HttpApplication
{
protected void Application_Start()
{
Database.SetInitializer(new TodoDbInit());
AreaRegistration.RegisterAllAreas();
RouteConfig.RegisterRoutes(RouteTable.Routes);
}
}
}
When I run my application, the database Is not created. I don't know why. Have I done something wrong?

You must make a call against your database in one of your controllers in order for it to be created (creation is on-demand). If you wish to manually create the database on application start see the answer posted here: Entity Framework code first, isn't creating the database
The following code is only setting the initializer that you wish to use against your database.
Database.SetInitializer(new TodoDbInit());
In order for it to actually be used you will need to create and access entities of your db context.

DbContext and Interface in HTTPPost action

I am using StructureMap for my dependency resolving. I am faced with an issue I don't know how to solve as the only way to make a form posting I understand will end up being without dependency injection which negate the whole essence of having StructureMap in my project.
The error is that I don't have Add method in my IdbContext Model. Below is my approach.
I have a Model named Module defined as below
public class Module
{
public virtual int ID { get; set; }
public virtual string Name { get; set; }
public virtual DateTime? DateCreated { get; set; }
public virtual string ModuleDescription { get; set; }
}
and an interface defined as below.
public interface ISolnetDataSource
{
IQueryable<Module> Modules { get; }
void Save();
}
A DbContext like below
public class CMSDB : DbContext, ISolnetDataSource
{
public CMSDB() : base("DefaultConnection")
{
}
public DbSet<Module> Modules { get; set; }
void ISolnetDataSource.Save()
{
SaveChanges();
}
IQueryable<Module> ISolnetDataSource.Modules
{
get { return Modules; }
}
}
and my controller defined as
[HttpPost]
public ActionResult Index(CreateModulesViewModels module)
{
ViewBag.ListModule = _db.Modules.ToList();
if (ModelState.IsValid)
{
var model = new CreateModulesViewModels();
var CreateModule = new Module();
CreateModule.Name = module.Name;
CreateModule.ModuleDescription = module.ModuleDescription;
CreateModule.DateCreated = DateTime.Now;
//_db.modules.Add(CreateModule);
_db.Save();
return View(model);
}
return View(module);
}
The challenge I have with this is that I could'nt do _db.modules.Add(CreateModule) (the commented line in the controller) so as to add a new record. What I'm doing wrong. I want to do this using the best approach applicable.

What about:
_db.modules.Entry(CreateModule).State = System.Data.EntityState.Added;