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Using a Database Context in multiple projects within the same solution

I'm currently working on a program that is being used to generate PDF's and documents. There are two different use cases, one being an automated process and the second being a manual process where data can be edited via a front-end app.
The solution has 2 Projects in it, the first for the automated part, and the second for the manual part.
However, since the two processes make use of the same data and templates, I've split the solution into two parts, this will allow me to set it up in a way in which I only need to maintain models/templates once.
My database context looks like this:
using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace RefundTracker.Models
{
public class DatabaseContext : DbContext
{
public DatabaseContext()
:base("Prod")
{
}
public DbSet<Referral> Referrals { set; get; }
public DbSet<ReferralAppointment> ReferralAppointments { set; get; }
public DbSet<ReferralPayment> ReferralPayments { set; get; }
public DbSet<BankDetails> BankDetails { set; get; }
public DbSet<ReferralAppointment_History> ReferralAppointment_History { set; get; }
public DbSet<ReferralPayment_History> ReferralPayment_History { set ; get; }
public DbSet<IsInUse> IsInUse { set; get; }
}
}
In terms of projects, I have a project called "RefundTracker" and another called "MailMergeTPA".
The context provided above, together with all of the models, are located in the "RefundTracker" project.
I would like to make use of these models and context in the "MailMargeTPA" project as well.
I referenced the "RefundTracker" in "MailMergeTPA" project, however, no results when using the context here. (When I access a function that get a list of names for instance, I get the full list in "RefundTracker", however, I get no results when I use the same function in "MailMergeTPA".
Code Example:
public BankDetails GetBankDetails(Referral record)
{
string bName = record.bankName.Trim();
try
{
BankDetails bankDetails= new BankDetails();
List<BankDetails> bankDetails = new List<BankDetails>();
using (DatabaseContext db = new DatabaseContext())
{
bankDetails = db.BankDetails.SingleOrDefault(a => a.BankName == bName);
}
return bankDetails;
}
catch(Exception ex)
{
Console.WriteLine(ex.ToString());
return null;
}
I would like to make use of this exact function in both projects.
Could you kindly help me with some advice? (Please go easy on me in the comments, I'm still fairly new to EF)
I've tried referencing the project, no result.
I've read up on interfaces, however, I'm unsure as to how I would incorporate this.

what 's the use of creating a metadata class and a partial class for the model class c#

I just joined a new company and my manager just joined too, and he wants to change the way we program. basically do what he does. I'm wondering what's the difference, pros, cons, limitation and problems if there'll be any..here's the sample
namespace Models //this is the model part of from edmx
{
using System;
using System.Collections.Generic;
public partial class MyModelClass
{
public int ID { get; set; }
public Nullable<System.DateTime> PostDate { get; set; }
public string MyContent { get; set; }
}
}
this is the metadata:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace Models
{
public class MyModelMetaData
{
//he wants all data annotation here
public int ID { get; set; }
public Nullable<System.DateTime> PostDate { get; set; }
public string MyContent { get; set; }
}
}
this is the partial:
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Web;
namespace Models
{
[MetadataType(typeof(MyModelMetaData))]
public partial class MyModelClass or MyModelClassPartial
{
//He wants the programming algorithm to go here
}
}
Please enlightened me. and he wants to create different metadata and partial classes per model class..way too many files involved.
thank you..i need an answer as to why..if you think his method is good..I will do this..but if you think this will cause problem in the future and more coding will be involve..i need to know

The first class you show, the entity classes, are generated from the database every time you save the EDMX (or when you execute the T4 Template).
This causes the file containing public partial class MyClass under the EDMX to be regenerated. So you cannot alter it, because the next time someone refreshes a table or adds one, your changes are gone.
That's why entity classes are generated as a partial: so you can create another partial to the same class to do your modifications in.
However, if you want to annotate your entity's properties with metadata, you cannot redefine the same property in the other partial class: the same name can only be used by one member of a type. So you can't do this:
// Entity class
public partial class FooEntity
{
public string Name { get; set;}
}
// User-created partial class
public partial class FooEntity
{
[Required]
public string Name { get; set;}
}
Because that code expresses you want two properties named Name in the FooEntity class, which is not valid.
So you'll have to come up with another way to add metadata to the type. Enter the [MetadataType] attribute. This works by creating a new class with the same properties as the class to be annotated. Here, using reflection, the metadata is resolved based on member name.
So when you create a metadata class for the above annotation:
public class FooEntityMetadata
{
[Required]
public string Name { get; set;}
}
You can apply it to the user-created partial:
// User-created partial class
[MetadataType(typeof(FooEntityMetadata))]
public partial class FooEntity
{
}
And also, in the latter partial, you can add members that add functionality to the entity model. New ([NotMapped]) properties and new methods for example.

I think the one use could be to not pollute the main class.
For example if you have a lot of attribute for validation (using dataannotation) and you don't want to have them in the main class you could use the MetadataTypeAttribute for that.
Another use could be if your class is auto-generated and you need to add some decoration (more attributes) to your properties without changing the autogenerated code.

TFS allowing me to access just one class out of five classes in the same folder in .net

I'm very new to working with TFS(of course not with Visual Studio). I have 6 projects in same solution and one of the projects has a folder with 6 c-sharp classes in it. When i try to access these classes from inside of other projects ( which all are in the same solution) except one class other five classes don't appear in the intellisense.
I have manually added reference to this project in other project. Which is why I'm able to access one class but my confusion is why not other classes are accessible through intellisense.
Did I do something wrong. I did check-in whatever pending changes were there in the entire solution still no luck.
Your help will be highly appreciated
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using NS.GIS.PTC.Core.Entities;
namespace NS.GIS.PTC.WebServices.DataManagement.Model.Dtos
{
public class FieldDescriptionDto
{
public string Name
{
get;
set;
}
public string Type
{
get;
set;
}
public string Alias
{
get;
set;
}
public int Length
{
get;
set;
}
public bool IsSystem
{
get;
set;
}
public Domain Domain
{
get;
set;
}
}
}
here is the code and below is the code that is using it I have written it forcibly coz as u know its not appearing in intellisense
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using NS.GIS.PTC.Core.Entities;
using NS.GIS.PTC.WebService.DataManagement.Model.Dtos;
namespace NS.GIS.PTC.WebService.DataManagement.API.Model
{
internal static class FieldDescriptionExtension
{
internal static FieldDescriptionDto ToFieldDescriptionDto(this FieldDescription fieldDescription)
{
return new FieldDescriptionDto
{
Name = fieldDescription.Name,
Type = fieldDescription.Type,
Alias= fieldDescription.Alias,
};
}
}
}

Please check if all the classes are marked Public.
Check if their namespaces have been included.
Restart VS and try.
Forcibly use them and see if you get a squiggle to auto-include namespace etc.

Entity Framework DbContext code generation generates incorrect code

I'm using VS2010 with Entity Framework (file version is 4.4. product version is 5)
I have installed the EF5.x DbContext generator.
After creating my .edmx file, I right clicked on the empty space and added a new DbContext template, which generated the context.tt and .tt files.
However, in the .tt files, this is how the auto generated code looks like:
namespace DataObjects.EntityFramework.Models
{
using System;
using System.Collections.Generic;
public partial class SubSystem
{
public string SubSystemId { get; set; }
public string Description { get; set; }
public string Fmode { get; set; }
public Nullable<System.DateTime> LastBackup { get; set; }
}
}
The problem is that the using statements are inside the namespace, which gives rise to a compilation error.

Those compilation errors must be related to something else, because it's perfectly legal in C# to have using statements in the namespace.
Verify that you've added all of the correct references, such as EntityFramework.dll

The type or namespace name 'Column' could not be found

I'm sure that I'm missing something simple here.
I'm trying to follow a Code First Entity Framework tutorial which tells me to use some Data Annotations.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.ComponentModel.DataAnnotations;
namespace Model
{
public class Destination
{
public int DestinationId { get; set; }
[Required]
public string Name { get; set; }
public string Country { get; set; }
[MaxLength(500)]
public string Description { get; set; }
[Column(TypeName="image")]
public byte Photo { get; set; }
public List<Lodging> Lodgings { get; set; }
}
}
The compiler doesn't have any issues with the first two annotations but it doesn't seem to like: [Column(TypeName="image")].
Errors:
The type or namespace name 'Column' could not be found.
The type or namespace name 'ColumnAttribute' could not be found.
I'm using Visual Studio 2012 and Entity Frameworks 5.
Any suggestions?

In Entity Framework 4.3.1, ColumnAttribute is defined in System.ComponentModel.DataAnnotations namspace , which is available in EntityFramework.dll. So if you have a reference to that dll and a using statement to the namespace, you should be fine.
In Entity Framework 5, It is in System.ComponentModel.DataAnnotations.Schema namspace, So you need to add a reference to that in your class.
using System.ComponentModel.DataAnnotations.Schema;
You can read more detailed information about it here.

I had the correct using statements ...
I had this problem despite having the correct using statements.
In my case, my project was generated by dotPeek after decompiling a dll (the original source code was lost).
dotPeek created the project with a reference to a copy of EntityFramework.dll just sitting in some folder, not being managed by NuGet.
What worked for me was to remove the reference to EntityFramework, and re-add it using the NuGet console.