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Correct way to check if greedily-loaded Entity was loaded after context disposed?

Probably not pertinent, but I'm using:
.NET MVC 5.2.3 w/ Razor 3.2.3, Entity Framework 6.1.3 Code First, Visual Studio 2015.
Okay, in my controller method, I have--in essence, but dumbed down for conciseness:
using( var context = new MyContext() ) {
var person = context.Persons.Include( x => x.PostalCode ).FirstOrDefault();
return View(person);
}
Now, originally the Zip data entry property was not a foreign key...just whatever 5-digit string the user entered. Now, however, it's a foreign key, in essence, so that we can get postal-code information.
public string Zip { get; set; }
[ForeignKey("Zip")]
public virtual PostalCode PostalCode { get; set; }
Not ideal structure...I know...
But anyway, if the user has a postal-code recognized by our system, all great, everything loads. However, if the user has an unknown or invalid zip code, e.g. 00000, EF sees a non-null Foreign Key and this results in the following problem:
In my view-file (so after I've disposed of my context), I check the property of our greedily-loaded entity:
#if( person.PostalCode != null && person.PostalCode.IsInServiceArea ) {
<div>Service Area HTML</div>
}
Unfortunately, because of EF overriding my virtual property, even when there is no PostalCode, it's not NULL. So, when this code runs it throws an exception that the ObjectContext has been disposed of, which means that EF is trying to lazy-load an Entity even though it already tried to greedily load and should know it doesn't exist :(
The obvious solutions (please don't answer w/ these):
Validate zip codes on entry and only allow ones we know about and set unknown zip codes to NULL (I like this, but I don't have time to re-engineer this)
Get the value of IsInServiceArea while the context is opened and put it directly in my View Model so that I set the value before my context is disposed of. (This is actually what I'm planning to do, so I don't need this answer):
The Question
In Entity Framework, Code-First, what is the correct way to check to
see if a greedily loaded, LEFT OUTER JOIN'd entity, was loaded AFTER
the context is disposed of?
Based on answers I have found, (e.g. the below), I'm thinking it's likely that this is not possible without the context being open...but thought I'd ask anyway:
How to determine if Navigation Property in the Entity Framework is set without loading the related records

So, referring back to my comment, you can disable lazy-loading and proxy creation altogether. Just find the constructor(s) of your dbcontext type, and then add these two lines into the method:
this.Configuration.LazyLoadingEnabled = false;
this.Configuration.ProxyCreationEnabled = false;
This way you can disable it globally (whenever a context is created the ctor is run, these settings are applied).
Or, you can just disable it for one instance if you set these on the context object itself after it's created.

Alternatively let your context live through the entire request so that lazy loading can be fulfilled on the view.
Startup.Auth.cs
public void ConfigureAuth(IAppBuilder app)
{
MyContext Create() { return new MyContext(); }
app.CreatePerOwinContext(Create);
...
}
MyController.cs
var context = HttpContext.GetOwinContext().Get<MyContext>();
var person = context.Persons.Include( x => x.PostalCode ).FirstOrDefault();
return View(person);

The ObjectContext instance has been disposed and can no longer be used

I've seen this question asked a million times, but every single suggestion I've encountered I already seem to have covered.
I have entity framework in my MVC solution, and I have a 'repository' which attempts to retrieve a collection of MyObjects:
public static List<MyObject> GetMyObjects()
{
using (var context = new MyEntities())
{
return context.MyObjects.Include("Contact").OrderByDescending(o => o.Date).ToList();
}
}
I call this method as part of a controller action which attempts to serialize it:
public JsonResult All()
{
return Json(MyRepository.GetMyObjects(), JsonRequestBehavior.AllowGet);
}
And I get the following error:
The ObjectContext instance has been disposed and can no longer be used for operations that require a connection.
I don't know where to turn on this one, I appreciate entity framework 'lazy-loads' relational data sets if and when they're needed, and I appreciate attempting to serialize the whole collection would indeed attempt to load these (outside of the using statement), but I have the 'Include' there.
What I've Tried
I've tried the 'include', I've also ensured no other associations are part of the MyObject class (i.e. I have no other Include()s to write).

To avoid this you have some options.Don't declare your navigation properties as virtual or disable Lazy Loading behavior on your context. Lazy loading is enable by default and is achieved by creating instances of derived proxy types and then overriding virtual properties to add the loading hook. So, if you want to work with a serializer I recommend you turn off lazy loading:
public class YourContext : DbContext
{
public YourContext()
{
this.Configuration.LazyLoadingEnabled = false;
}
}
These links can help you to understand better what I explain in my answer:
Loading Related Entities
Requirements for Creating POCO Proxies
If you remove the virtual keyword from your navigation properties, the POCO entity not meet the requirements described in the second link, so, EF won't create a proxy class to lazy load your navigation properties. But if you disabled lazy loading, even when your navigation properties are virtual, they won't be loaded in any entity. It's good idea disable lazy loading when you are using a serializer. Most serializers work by accessing each property on an instance of a type.
As a third option you could use the JsonIgnore attribute on your navigation properties that you don't want to be serialized as part of your entity, but as I said before, the best option is disable lazy loading.

When you use Include and using Lazy loading, and wrap the dbContext in a Using statement, then once it tries to get the linked objects, the dbContext is already disposed.
You can try eager loading of the navigation property like this:
IQueryable<MyObjects> query = db.MyObjects.Include(m => m.Contact);
Or you could take out the Using statement, as it is limiting your lazy loading...

I had the same problem and solved like below;
I created a new object and put the values I am gonna use after getting object from db.
Example Code:
var listFromDb= db.XTable.Where(x => x.Id > 5).ToList();
var list = new List<Package>();
foreach (var item in listFromDb)
{
var a = new Package()
{
AccountNo = item.AccountNo,
CreateDate = item.CreateDate,
IsResultCreated = item.IsResultCreated,
};
list.Add(a);
}

EntityFramework Not Loading Related Data

I have these entities:
public class Company : PrimaryKey
{
public string Name {get;set;}
public virtual Account Account {get;set;}
}
public class Account
{
[Key]
public Guid CompanyId { get; set; }
public virtual Company Company {get;set;}
}
I use these configurations:
modelBuilder.Entity<Company>()
.HasOptional(c => c.Account)
.WithRequired(a => a.Company)
.WillCascadeOnDelete();
Now, I have two projects, one is a test bench project which is a Console Application with a DbContext and a Repository, the second is the full blown production project which is a MVC 4 in which I use Dependancy Injection to create a Repository .InTransientScope() which in turn loads a new context each time it is called.
Both have exactly the same contexts and repositories (the product obviously has Interfaces).
in the test bench when I call this:
_repository.GetById<Company>(id);
All of it properties are filled out, i.e. eager loading
in the production when I call the same line, nothing is loaded and its not loaded till I created another function which does this:
_dbContext.Companies.Include("Account").FirstOrDefault(x => x.Id.Equals(id));
Of which, when executed does provide all the Account information, but funnily bar any other navigation properties that Account contains!!! Even though I have disable LazyLoading, it still doesn't work.
This is surprising because both projects are fundamentally the same, bar the use of the IoC DI in one of them....
Why is this happening? How can I specify in a predominantly generic Repository to eager load all this information at the Controllers preference....?
Break Points
I set break points in both projects too look at the ADO.NET call to the database and the sql statement that was executed, in the test bench it did go off and call the information, in the production it did not show any joins or anything of that nature what so ever.
Other Things Tried
I tried accessing the navigation property directly when loading it from the database:
var acc = _repository.GetById<Company>(id).Account;
It still says null. So my repository/context is not even loading any related data when asked for it.... what is going on?!
Definitions
_repository.GetById<Company>(id);
is:
public T GetById<T>(Guid id)
{
return _dbContext.Set<T>().FirstOrDefault(x => x.Id.Equals(id));
}

It's working now, I have no idea why.. I haven't tampered with anything. The only thing that I have, was to put .InTransientScope() onto IDbContextFactory<MyContext>
I actually enabled all Lazy Loading everywhere I could, and it now works.... but it's strange that when I started on the Production project I never even tampered with Lazy Loading at all, but since I extented the Model and added modelBuilder stuff I have had to specifically tell it to Lazy Load.

Lazy loading not working for POCO classes in Entity Framework

Please help me, I am new to EF.Lazy loading for POCO objects doesn't seem to be working.
My POCO classes are in a sepearte assembly, other than the one one for Data access(i.e DAL)
The Data Acess layer simply wraps the calls made to the EF's object context. Please see the code below
public FilterMaster GetFilter(long ID)
{
FilterMaster entity = new FilterMaster();
try
{
using (var context = new RadarEntities())
{
//context.ContextOptions.LazyLoadingEnabled = false;
//context.ContextOptions.ProxyCreationEnabled = true;
entity = context.FilterMasters.SingleOrDefault(filter => filter.ID == ID);
//context.FilterMasters.Include(
context.LoadProperty(entity, "SQLQuery");
}
}
When DAL call is completed, the ObjectContext is lost, and when I tried to fetch the related child objects of the Root POCO class, I get null.
I've tried explicitly enabling ProxyCreation, EnabledLazyLoading, checked the proxy clases generated are not sealed and all the related properties are marked virtual (as suggested on some other links).
-As the lazy load was not working, I thought of eagerly loading all the related POCO objects, so tried invoking LoadProperty method, which works.
Q1: Am I Imissing something the lazy loading isn't working?
Q2: If I want to expelictly load all the related child objects the will have to call the LoadProperty method for all properties or there is any simpler way?

You are disposing your ObjectContext. This is what is preventing you from using LazyLoading. If you need LazyLoading, the class containing GetFilter should create an ObjectContext when it is created, implement IDisposable, and dispose of the ObjectContext when it is disposed.

Q1: Am I Imissing something the lazy loading isn't working?
It's working but there is no magic involved - underneath a proxy is created for you which will try to retrieve the property value from the database for you on the first access.
For EF the database connection is represented by the context, which you currently dispose automatically at the end of your using block. Without database connection EF cannot lazily retrieve the properties and hence lazy loading won't work.
You will have to keep the context alive until you have accessed all the properties you need to access for lazy loading, or alternatively eagerly load those properties.
Q2: If I want to explicitly load all the related child objects the
will have to call the LoadProperty method for all properties or there
is any simpler way?
Yes, you can specify an Include() query to eagerly retrieve properties, in your case that would be:
entity = context.FilterMasters
.Include("SQLQuery")
.SingleOrDefault(filter => filter.ID == ID);

How do I map entities with lazy-loaded properties (without causing them to load)?

I'm using EF 4.1 and code-first in an MVC project, and AutoMapper to map entities to view models.
Prior to using code-first I was able to exclude navigation properties in order to prevent anything from being loaded that wasn't already. I'm using .Include() in my queries to include the references that I need in order to avoid additional database round-trips.
However, with code-first my entity only exposes an entity property (or ICollection if there are more than one). How can I know whether it has been loaded without triggering the load?
Assuming this can be done, is there a way to make this the default behavior for AutoMapper, so that I do not have to explicitly exclude members on every single entity?

You can check whether a reference or collection navigation property of an entity has been loaded by:
bool isLoaded1 = dbContext.Entry(entity).Reference(e => e.MyReferenceProperty)
.IsLoaded();
bool isLoaded2 = dbContext.Entry(entity).Collection(e => e.MyCollectionProperty)
.IsLoaded();

EF Code First does lazy loading only for properties marked as virtual (it can override those and place DynamicProxy instead of it). If you don't make your property virtual, you will turn off lazy loading for that property.

You should be able to explicitly load them by turning off lazy-loading:
using(var context = new FooBarEntities())
{
context.ContextOptions.LazyLoadingEnabled = false;
Foo foo = context.Foo.Where(x => x.Id == myId).Single();
...
if(!foo.Bars.IsLoaded)
{
foo.Bars.Load();
}
//do something with foo.Bars here
}