I'm using Reverse Engineered Code First code and see stubs like:
public class User
{
public User()
{
this.Addresses = new List<Address>();
...
}
public int ID { get; set; }
...
}
When, based on this question, i'd expect to see partial classes.
Wouldn't this change the preferred way of extending the generated classes with my own code (which is very nicely summarized in the linked answer, btw)?
thx
Our aim was to generate the simplest classes possible, as close to what you would write by hand as we could. There is no problem changing them to be partial - that's exactly the kind of reason we made the generation customizable.
~Rowan
There is a way to customize the output of the entity objects by changing the TT files.
Rowan Miller has an excellent blog post on how to do it.
In your example, you can update the Entity.TT file that's int he template
From this:
public class <#= efHost.EntityType.Name #>
To this:
public partial class <#= efHost.EntityType.Name #>
and it will create the partial classes you're looking for.
Related
i'm new to mvc 5, and I would like to build an asp.net application to interact with an existing database. I'm using VIsual studio 2013 and Entity Framework 6.
I've generated an ADO.net Entity Data Model from an existing database and I'm currently trying to find out the best way to make data validations, to avoid wrong inputs (let's take as example the field Email from entity Users).
The right way seems to be to use Annotations on partial classes. But i don't know how to add an annotation (on the new partial class that i created for that) if the original property declaration is on the autogenerated file.
The autogenerated class, looks like:
namespace Test.Models
{
...
public partial class Users
{
public string Email { get; set; }
}
...
}
Following the idea behind [this post] (Add data annotations to a class generated by entity framework), i'm trying to make a partial class to write the annotations there, like that:
namespace Test.Models
{
using System.ComponentModel.DataAnnotations;
[MetadataType(typeof(UsersMetaData))]
public partial class Users
{
[Someanotations]
public string Email { get; set; }
}
}
But on the partial class, i get:
1) Error on the line of "[MetadataType(typeof(UsersMetadata))]", saying that UsersMetadata could not be found, and
2) Error on the line where "public string email", saying that the property is already declared (which sounds logic for me).
How should i annotate on the new partial class the property that is declared on the autogenerated model?
It is possible to define a Regex to be used on the anotation?
Thanks for your time,
John
You're almost there. UserMetadata is actually another class that you apply the annotations to. I usually put both of these in the same file.
[MetadataType(typeof(UsersMetaData))]
public partial class Users
{
}
class UsersMetaData
{
[Someanotations]
public string Email { get; set; }
}
I am playing around building some buildingblocks based on database tables.
So I've created an UsersManager and a ValidationManager both based on the EDMX "templates".
I'd really like to loose couple those two components with MEF. But therefore i need to create Interfaces of the entityobjects exposed in the ValidationManager.
Is there an easy way of creating those Interfaces, in that manner i can still use the EDMX generated classes?
Thanx,
Paul
Using an example of a database with a Product Table, is this what you're trying to achieve....
but still use generated entity classes (using either the standard EF generator or another POCO generator of some sort).
I'm not sure - as you mention MEF and I don't see it being directly related.
The generated entity classes are partial classes which will allow you to extend the generated class which in this case you want to extend to implement an interface.
Presuming the following interface is going to be used to introduce the layer of abstraction...
public interface IEntity {
public bool IsDeleted { get; set; }
}
Create a new class file with and extended Product class...
public partial class Product : IEntity {
public bool IsDeleted {
get {
throw new NotImplementedException();
}
set {
throw new NotImplementedException();
}
}
}
You have now extended your generated entity Product with the partial class custom code - and you can use it as normal through EF.
Now instead of your UserManager and ValidationManager classes having a hard reference to Product, instead they'll only have reference to IEntity.
If I didn't understand the question, please provide more details on exactly it is you want to do.
A models already exists. They are situated in another project. Where I should put DataAnotations in that project or my one? Should I use partial classes? I would like to put DataAnatation because I want javascript validation to work on client.
You can't use partial classes across assemblies, so that option is out.
You can create DTOs (data transfer objects) that are copies of the ones in the other assembly, annotate them and map.
For easy mapping you can use a tool like auto mapper. If the property names match, it will essentially do all the work for you.
Create a partial class for your Model. like this:
[MetadataType(typeof(Log_Validation))]
public partial class Log : IEntity
{
}
then create a new class Log_Validation which does all the data annotations stuff.
public class Log_Validation
{
[DisplayName("Level")]
[Required(ErrorMessage = "Please provide a level")]
public String Level { get; set; }
}
I'm using Ria service class library. This contains 2 library named RiaClasslibrary RiaClasslibrary.Web.
Riaclasslibrary.Web contains ADO.NET entity data model and named BaseModel. BaseModelcontains tPage class.
My problem is
I'm inserting separated tPage class. This class contains 2 public property. show below
public sealed partial class tPage : EntityObject
{
public List<tPage> Children { get; set; }
public tPage Parent { get; set; }
public Boolean IsSelected { get; set; }
}
After I'm inserting DomainService and building RiaClasslibrary.Web class library. But ria service generated code doesn't contains above properties.
You have a question. Why you separate tPage class. You simply insert those 3 property in Modelbase.Designer code.
My answer is: Database doesn't contain those 3 property and If I'm inserting properties in the code, properties removed after updating Entity Model.
#ebattulga
I don't know if you still have this issue, but I will post the answer because I came to similar issue.
The answer for
After I'm inserting DomainService and
building RiaClasslibrary.Web class
library. But ria service generated
code doesn't contains above
properties.
is quite easy but hard to find.
You can read here in section "Shared Code" http://www.silverlightshow.net/items/WCF-RIA-Services-Part-5-Metadata-and-Shared-Classes.aspx
If you want to see custom properties from partial classes on the Client you have to rename class file name from MyClass.cs to simply MyClass.shared.cs. This will create partial class in the code generated Client side.
HTH
Daniel SkowroĊski
I'm using entity framework designer to build entities. I found the designer really hard to use because it overwrite all your manually change after each model update using the designer. How did you round off this problem? Thanks!
What sorts of things are you manually changing? The entity still has to be mappable to the database schema.
You can extend or add functionality by declaring a partial class.
Don't make any change to the entities in the generated file -- I think it says that in the header.
All of the entities are generated as partial classes, which means you can declare "more" of the class elsewhere.
Here is an example:
public partial class Name
{
public string First { get; set; }
}
public partial class Name
{
public string Last { get; set; }
}
Although I have two different class declarations, potentially in different files and folders within the project, it gets compiled as one class.
I can now use the Name class like this:
var name = new Name();
name.First = "Jane";
name.Last = "Doe";
As you can see, the properties from both declarations are unified in an object of type Name.
To apply this to EF, leave the partial entity class alone, and declare a separate partial class with the same name to add functionality.
There is an alternative third-party tool. For more information, refer this. Currently, Devart Entity Developer doesn't include the Update From Database functionality. The Update From Database feature is on our roadmap.