Repository pattern - using EF Fluent API use EntityTypeConfiguration sub-file mapping between configuration Model

EF class EntityTypeConfiguration is a very useful class, in nop to use this class to sub-sub-file configuration file mapping relationship Commerence in Model. Today I will talk about using the Repository pattern implementation example EntityTypeConfiguration in Entity Framework Code First in.

background

To simplify we will only use two tables: Classification Category, product type Product. The final project is structured as follows:

Note: EfRepPatTest.Entity and EfRepPatTest.Data class library project, EfRepPatTest.Implementation a console project. EfRepPatTest.Data project requires a reference to the Entity Framework class library.

BaseEntity.cs

BaseEntity create a base class for all entities, some common properties inside the package.

1. public class BaseEntity<T>
2. {
3. public T Id { get; set; }
4. }

This means that all entities have a field for the Id, the generic type which can meet all types of situations.

IRepository.cs:

The following defines a generic interface to the IRepository, including a generic add, delete, change.

1. public interface IRepository<TEntity> where TEntity:class
2. {
3. IQueryable<TEntity> GetAll();
4. TEntity GetById(object id);
5. void Insert(TEntity entity);
6. void Update(TEntity entity);
7. void Delete(TEntity entity);
8. }

Category.cs:

Entity classes classes

1. public class Category:BaseEntity<int>
2. {
3. public virtual string Name { get; set; }
5. public List<Product> Products { get; set; }
6. }

Product.cs:

Physical products category

1. public class Product:BaseEntity<long>
2. {
3. public virtual int CategoryId { get; set; }
4. public virtual Category Category { get; set; }
5. public virtual stringName{ get;set;}
6. public virtual int MinimumStockLevel { get; set; }
7. }

IDbContext.cs:

Some interfaces IDbContext EF package public interface method.

1. public interface IDbContext
2. {
4. IDbSet<TEntity> Set<TEntity>() where TEntity:class;
5. int SaveChanges();
6. void Dispose ();
7. }

DataContext.cs:

1. public class DataContext: DbContext,IDbContext
2. {
3. public new IDbSet<TEntity> Set<TEntity>() where TEntity : class
4. {
5. return base.Set<TEntity>();
6. }
7. }

CategoryMap.cs:

Classification map class inherits EntityTypeConfigureation <T>

1. public class CategoryMap:EntityTypeConfiguration<Category>
2. {
3. public CategoryMap()
4. {
5. ToTable("Category");
6. HasKey(c => c.Id).Property(c => c.Id).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);
7. Property(c => c.Name).IsRequired().HasMaxLength(50);
8. }
9. }

ProductMap.cs:

Product category mapping class inherits from EntityTypeConfigureation <T>

1. public class ProductMap:EntityTypeConfiguration<Product>
2. {
3. public ProductMap()
4. {
5. ToTable("Product");
6. HasKey(p => p.Id).Property(p => p.Id).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);
7. //CategoryId as foreign key
8. HasRequired(p => p.Category)
9. .WithMany(c=>c.Products)
10. .HasForeignKey(p => p.CategoryId);
11. Property(p => p.Name).IsRequired().HasMaxLength(100);
12. Property(p => p.MinimumStockLevel);
13. }
14. }

In DataContext class method override OnModelCreating order together with our new EF's Map configuration file, add the following code:

1. modelBuilder.Configurations.Add(new CategoryMap());
2. modelBuilder.Configurations.Add(new ProductMap());
3. base.OnModelCreating(modelBuilder);

The optimization code can look above, may be utilized reflection automatically add the EF Map configuration file as follows:

1. public class DataContext: DbContext,IDbContext
2. {
3. public new IDbSet<TEntity> Set<TEntity>() where TEntity : class
4. {
5. return base.Set<TEntity>();
6. }
8. protected override void OnModelCreating(DbModelBuilder modelBuilder)
9. {
10. var typesToRegister = Assembly.GetExecutingAssembly().GetTypes()
11. .Where(type => !String.IsNullOrEmpty(type.Namespace))
12. .Where(type => type.BaseType != null && type.BaseType.IsGenericType &&
13. type.BaseType.GetGenericTypeDefinition() == typeof(EntityTypeConfiguration<>));
14. foreach (var type in typesToRegister)
15. {
16. dynamicconfigurationInstance = Activator.CreateInstance(type);
17. modelBuilder.Configurations.Add(configurationInstance);
18. }
20. base.OnModelCreating(modelBuilder);
21. }
23. }

The advantage is that after the new entity plus EF Map class, without modification DataContext.

RepositoryService.cs：

IRepositroy RepositoryService one particular implementation of the interface, the data access using the EF IDbContext.

1. public class RepositoryService<TEntity>:IRepository<TEntity> where TEntity:class
2. {
3. private IDbContext Context;
5. private IDbSet<TEntity> Entities
6. {
7. get { return this.Context.Set<TEntity>(); }
8. }
10. public RepositoryService(IDbContext context)
11. {
12. this.Context = context;
14. }
16. public IQueryable<TEntity> GetAll()
17. {
18. return Entities.AsQueryable();
19. }
21. public TEntity GetById(object id)
22. {
23. return Entities.Find(id);
24. }
26. public void Insert(TEntity entity)
27. {
28. Entities.Add(entity);
29. }
31. public void Update(TEntity entity)
32. {
33. if (entity == null)
34. throw new ArgumentNullException("entity");
36. this.Context.SaveChanges();
37. }
39. public void Delete(TEntity entity)
40. {
41. Entities.Remove(entity);
42. }
44. public void Dispose ()
45. {
46. Dispose(true);
47. GC.SuppressFinalize(this);
48. }
49. protected virtual void Dispose(bool disposing)
50. {
51. if (disposing)
52. {
53. if (this.Context != null)
54. {
55. this.Context.Dispose();
56. this.Context = null;
57. }
58. }
59. }
60. }

Create a new class DataBaseInitializer to initialize the class EF Code First database access.

1. public class DataBaseInitializer : IDatabaseInitializer<DataContext>
2. {
3. public void InitializeDatabase(DataContext context)
4. {
5. context.Database.CreateIfNotExists();
6. }
7. }

Create a new console application to test the above code Program.cs:

1. class Program
2. {
3. static void Main(string[] args)
4. {
5. var context = new DataContext();
6. var dataBaseInitializer = new DataBaseInitializer();
7. dataBaseInitializer.InitializeDatabase(context);
9. var categoryRepository = new RepositoryService<Category>(context);
11. //Adding category in the category entity
12. var category = new Category ()
13. {
14. Name = "Baverage"
15. };
16. var products = new List<Product>();
18. //Adding product in the product entity
19. var product = new Product()
20. {
21. Name = "Soft Drink A",
22. MinimumStockLevel = 50
23. };
24. products.Add(product);
26. product = new Product()
27. {
28. Name = "Soft Drink B",
29. MinimumStockLevel = 30
30. };
31. products.Add(product);
33. category.Products = products;
35. //Insert category and save changes
36. categoryRepository.Insert(category);
37. context.SaveChanges();
39. ///////////////////////////////////////////////////////////////////////////////
40. /////////////////For the next project we shall add Dependency Injection////////
41. ////////////////But now we have add a Service layer for test manually//////////
42. ///////////////////////////////////////////////////////////////////////////////
43. IProductService productRepository = new ProductService();
45. Console.WriteLine("\n");
46. Console.WriteLine("Product List:");
47. Console.WriteLine("-------------------------------------------------");
48. foreach (var product1 in productRepository.GetAll())
49. {
50. Console.WriteLine(string.Format("Product Name : {0}",product1.Name));
51. if (product1.Id == 9)
52. {
54. product1.Name = "Soft Drink AAA";
55. productRepository.Update(product1);
56. }
57. }
58. Console.WriteLine("Press any key to exit");
59. Console.ReadKey();
60. }
61. }

Add a link to a database in the configuration file.

App.config:

1. <?xml version="1.0" encoding="utf-8"?>
2. <configuration>
3. <configSections>
4. <!-- For more information
5. on Entity Framework configuration, visit
6. http://go.microsoft.com/fwlink/?LinkID=237468 -->
7. <section name="entityFramework"
8. type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection,
9. EntityFramework, Version=4.4.0.0, Culture=neutral,
10. PublicKeyToken=b77a5c561934e089"
11. requirePermission="false" />
12. </configSections>
13. <entityFramework>
14. <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory,
15. EntityFramework" />
16. </entityFramework>
18. <connectionStrings>
19. <add name="DataContext"
20. providerName="System.Data.SqlClient"
21. connectionString="Data
22. Source=YourSERVER;Initial Catalog=EfDBExistRepository;Integrated
23. Security=True;MultipleActiveResultSets=True;"/>
25. </connectionStrings>
26. </configuration>

Note: The database link node named "DataContext", and just write our own class "DataContext" the same name. EF framework so you can automatically find this database link information.

Reference: http://www.codeproject.com/Articles/561584/Repository-Pattern-with-Entity-Framework-using