एंटिटी फ्रेमवर्क कोड फर्स्ट पर डेटा एक्सेस लेयर लागू करना

namespace TestApp.Models { public partial class UsersContext : DbContext { public UsersContext() : base("Name=UsersContext") { } public DbSet<User> Users { get; set; } protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Configurations.Add(new UserMap()); } } }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
     

  public interface IDbContext { IQueryable<T> Find<T>() where T : class; void MarkAsAdded<T>(T entity) where T : class; void MarkAsDeleted<T>(T entity) where T : class; void MarkAsModified<T>(T entity) where T : class; void Commit(bool withLogging); //      void Rollback(); //       void EnableTracking(bool isEnable); EntityState GetEntityState<T>(T entity) where T : class; void SetEntityState<T>(T entity, EntityState state) where T : class; //         DbChangeTracker GetChangeTracker(); DbEntityEntry GetDbEntry<T>(T entity) where T : class; }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
     

 namespace DataAccess.DbContexts { public class DemoAppDbContext : DbContext, IDbContext { public static User CurrentUser { get; set; } private readonly ILogger _logger; #region Context Entities public DbSet<EntityChange> EntityChanges { get; set; } public DbSet<User> Users { get; set; } #endregion static DemoAppDbContext() { //  Database.SetInitializer(new CreateDBContextInitializer()); } //       public static void Seed(DemoAppDbContext context) { //     var defaultUser = new User { Email = "UserEmail@email.ru", Login = "login", IsBlocked = false, Name = "Vasy Pupkin" }; context.Users.Add(defaultUser); context.SaveChanges(); } public DemoAppDbContext(string nameOrConnectionString) : base(nameOrConnectionString) { //   _logger = new Logger(this); } protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Configurations.Add(new EntityChangeMap()); modelBuilder.Configurations.Add(new UserMap()); } public void MarkAsAdded<T>(T entity) where T : class { Entry(entity).State = EntityState.Added; Set<T>().Add(entity); } public void MarkAsDeleted<T>(T entity) where T : class { Attach(entity); Entry(entity).State = EntityState.Deleted; Set<T>().Remove(entity); } public void MarkAsModified<T>(T entity) where T : class { Attach(entity); Entry(entity).State = EntityState.Modified; } public void Attach<T>(T entity) where T : class { if (Entry(entity).State == EntityState.Detached) { Set<T>().Attach(entity); } } public void Commit(bool withLogging) { BeforeCommit(); if (withLogging) { _logger.Run(); } SaveChanges(); } private void BeforeCommit() { UndoExistAddedEntitys(); } // ,      ,        private void UndoExistAddedEntitys() { IEnumerable<DbEntityEntry> dbEntityEntries = GetChangeTracker().Entries().Where(x => x.State == EntityState.Added); foreach (var dbEntityEntry in dbEntityEntries) { if (GetKeyValue(dbEntityEntry.Entity) > 0) { SetEntityState(dbEntityEntry.Entity, EntityState.Unchanged); } } } //      public void Rollback() { ChangeTracker.Entries().ToList().ForEach(x => x.Reload()); } public void EnableTracking(bool isEnable) { Configuration.AutoDetectChangesEnabled = isEnable; } public void SetEntityState<T>(T entity, EntityState state) where T : class { Entry(entity).State = state; } public DbChangeTracker GetChangeTracker() { return ChangeTracker; } public EntityState GetEntityState<T>(T entity) where T : class { return Entry(entity).State; } public IQueryable<T> Find<T>() where T : class { return Set<T>(); } public DbEntityEntry GetDbEntry<T>(T entity) where T : class { return Entry(entity); } public static int GetKeyValue<T>(T entity) where T : class { var dbEntity = entity as IDbEntity; if (dbEntity == null) throw new ArgumentException("Entity should be IDbEntity type - " + entity.GetType().Name); return dbEntity.GetPrimaryKey(); } } }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
     

  interface IRepository<T> where T : class { DemoAppDbContext CreateDatabaseContext(); List<T> GetAll(); T Find(int entityId); T SaveOrUpdate(T entity); T Add(T entity); T Update(T entity); void Delete(T entity); //    DbEntityValidationResult Validate(T entity); //     string ValidateAndReturnErrorString(T entity, out bool isValid); }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
     

 namespace DataAccess.Repositories { public abstract class BaseRepository<T> : IRepository<T> where T : class { private readonly IContextManager _contextManager; protected BaseRepository(IContextManager contextManager) { _contextManager = contextManager; } public DbEntityValidationResult Validate(T entity) { using (var context = CreateDatabaseContext()) { return context.Entry(entity).GetValidationResult(); } } public string ValidateAndReturnErrorString(T entity, out bool isValid) { using (var context = CreateDatabaseContext()) { DbEntityValidationResult dbEntityValidationResult = context.Entry(entity).GetValidationResult(); isValid = dbEntityValidationResult.IsValid; if (!dbEntityValidationResult.IsValid) { return DbValidationMessageParser.GetErrorMessage(dbEntityValidationResult); } return string.Empty; } } //    .   using public DemoAppDbContext CreateDatabaseContext() { return _contextManager.CreateDatabaseContext(); } public List<T> GetAll() { using (var context = CreateDatabaseContext()) { return context.Set<T>().ToList(); } } public T Find(int entityId) { using (var context = CreateDatabaseContext()) { return context.Set<T>().Find(entityId); } } //  .    ,       protected virtual void BeforeSave(T entity, DemoAppDbContext db) { } public T SaveOrUpdate(T entity) { var iDbEntity = entity as IDbEntity; if (iDbEntity == null) throw new ArgumentException("entity should be IDbEntity type", "entity"); return iDbEntity.GetPrimaryKey() == 0 ? Add(entity) : Update(entity); } public T Add(T entity) { using (var context = CreateDatabaseContext()) { BeforeSave(entity, context); context.MarkAsAdded(entity); context.Commit(true); } return entity; } public T Update(T entity) { using (var context = CreateDatabaseContext()) { var iDbEntity = entity as IDbEntity; if (iDbEntity == null) throw new ArgumentException("entity should be IDbEntity type", "entity"); var attachedEntity = context.Set<T>().Find(iDbEntity.GetPrimaryKey()); context.Entry(attachedEntity).CurrentValues.SetValues(entity); BeforeSave(attachedEntity, context); context.Commit(true); } return entity; } public void Delete(T entity) { using (var context = CreateDatabaseContext()) { context.MarkAsDeleted(entity); context.Commit(true); } } } }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
     

 namespace DataAccess.Models { public class User : IDbEntity { public User() { this.EntityChanges = new List<EntityChange>(); } public int UserId { get; set; } [Required(AllowEmptyStrings = false, ErrorMessage = @"Please input Login")] [StringLength(50, ErrorMessage = @"Login    50- ")] public string Login { get; set; } [Required(AllowEmptyStrings = false, ErrorMessage = @"Please input Email")] [StringLength(50, ErrorMessage = @"Email    50- ")] public string Email { get; set; } [Required(AllowEmptyStrings = false, ErrorMessage = @"Please input Name")] [StringLength(50, ErrorMessage = @"    50- ")] public string Name { get; set; } public bool IsBlocked { get; set; } public virtual ICollection<EntityChange> EntityChanges { get; set; } public override string ToString() { return string.Format(": User; :{0}, UserId:{1} ", Name, UserId); } public int GetPrimaryKey() { return UserId; } } }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
     

 namespace DataAccess.Repositories { public class UsersRepository : BaseRepository<User> { public UsersRepository(IContextManager contextManager) : base(contextManager) { } public User FindByLogin(string login) { using (var db = CreateDatabaseContext()) { return db.Set<User>().FirstOrDefault(u => u.Login == login); } } public bool ExistUser(string login) { using (var db = CreateDatabaseContext()) { return db.Set<User>().Count(u => u.Login == login) > 0; } } public User GetByUserId(int userId) { using (var db = CreateDatabaseContext()) { return db.Set<User>().SingleOrDefault(c => c.UserId == userId); } } public User GetFirst() { using (var db = CreateDatabaseContext()) { return db.Set<User>().First(); } } } }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
     

 namespace DataAccess.Container { public class RepositoryContainer { private readonly IContainer _repositoryContainer = new Container(); public static readonly RepositoryContainer Instance = new RepositoryContainer(); private RepositoryContainer() { } public T Resolve<T>() where T : class { return _repositoryContainer.Resolve<T>(); } public void Register<T>(T entity) where T : class { _repositoryContainer.Register(entity); } } } namespace DataAccess.Container { public static class RepositoryContainerFactory { public static void RegisterAllRepositories(IContextManager dbContext) { RepositoryContainer.Instance.Register(dbContext); RepositoryContainer.Instance.Register(new EntityChangesRepository(dbContext)); RepositoryContainer.Instance.Register(new UsersRepository(dbContext)); } } }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
     

 namespace DataAccess.Interfaces { public interface IContextManager { DemoAppDbContext CreateDatabaseContext(); } }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
     

 using DataAccess.Interfaces; namespace DataAccess.DbContexts { public class ContextManager : IContextManager { private readonly string _connectionString; public ContextManager(string connectionString) { _connectionString = connectionString; } public DemoAppDbContext CreateDatabaseContext() { return new DemoAppDbContext(_connectionString); } } }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
     

 namespace DataAccess.Interfaces { internal interface ILogger { void Run(); } }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
     

  public class Logger : ILogger { Dictionary<EntityState, string> _operationTypes; private readonly IDbContext _dbContext; public Logger(IDbContext dbContext) { _dbContext = dbContext; InitOperationTypes(); } public void Run() { LogChangedEntities(EntityState.Added); LogChangedEntities(EntityState.Modified); LogChangedEntities(EntityState.Deleted); } private void InitOperationTypes() { _operationTypes = new Dictionary<EntityState, string> { {EntityState.Added, ""}, {EntityState.Deleted, ""}, {EntityState.Modified, ""} }; } private string GetOperationName(EntityState entityState) { return _operationTypes[entityState]; } private void LogChangedEntities(EntityState entityState) { IEnumerable<DbEntityEntry> dbEntityEntries = _dbContext.GetChangeTracker().Entries().Where(x => x.State == entityState); foreach (var dbEntityEntry in dbEntityEntries) { LogChangedEntitie(dbEntityEntry, entityState); } } private void LogChangedEntitie(DbEntityEntry dbEntityEntry, EntityState entityState) { string operationHash = HashGenerator.GenerateHash(10); int enitityId = DemoAppDbContext.GetKeyValue(dbEntityEntry.Entity); Type type = dbEntityEntry.Entity.GetType(); IEnumerable<string> propertyNames = entityState == EntityState.Deleted ? dbEntityEntry.OriginalValues.PropertyNames : dbEntityEntry.CurrentValues.PropertyNames; foreach (var propertyName in propertyNames) { DbPropertyEntry property = dbEntityEntry.Property(propertyName); if (entityState == EntityState.Modified && !property.IsModified) continue; _dbContext.MarkAsAdded(new EntityChange { UserId = DemoAppDbContext.CurrentUser.UserId, Created = DateTime.Now, OperationHash = operationHash, EntityName = string.Empty, EntityType = type.ToString(), EntityId = enitityId.ToString(), PropertyName = propertyName, OriginalValue = entityState != EntityState.Added && property.OriginalValue != null ? property.OriginalValue.ToString() : string.Empty, ModifyValue = entityState != EntityState.Deleted && property.CurrentValue != null ? property.CurrentValue.ToString() : string.Empty, OperationType = GetOperationName(entityState), }); } } }
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
     

 private void InitDefaultUser() { User defaultUser = RepositoryContainer.Instance.Resolve<UsersRepository>().GetFirst(); DemoAppDbContext.CurrentUser = defaultUser; }