我在开始使用 AutoFac 和 IoC 时遇到了一些问题。我们有一个工作应用程序,但是,我从头开始使用这个应用程序,看不出两者之间的差异在哪里。
我正在使用一个简单的 AJAX 页面对此进行测试,该页面通过 ServiceStack API 调用服务层。当使用 MockRepositories 时,它工作得很好,所以我知道事情的那一面是有效的。
但是,当我用使用实体框架的模拟替换模拟时,尽管所有注册似乎都正确且有效,但我收到错误“在创建模型时无法使用上下文”。
我在下面包含了我的代码:
public class SomeObject
{
public int Id { get; set; }
}
public class IoCExampleContext : DbContext, IIoCExampleContext
{
public IDbSet<SomeObject> SomeObjects { get; set; }
static IoCExampleContext()
{
Database.SetInitializer(new IoCExampleDatabaseInitilizer());
}
public IoCExampleContext(string connectionStringName)
: base(connectionStringName)
{
Configuration.ProxyCreationEnabled = false;
}
public IoCExampleContext()
: this("name=IoCExample")
{}
public string ConnectionString
{
get { return Database.Connection.ConnectionString; }
}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
BuildModels(modelBuilder);
}
private void BuildModels(DbModelBuilder builder)
{
var typeToUse = typeof(SomeObjectModelBuilder);
var namespaceToUse = typeToUse.Namespace;
var toReg = Assembly
.GetAssembly(typeToUse)
.GetTypes()
.Where(type => type.Namespace != null && type.Namespace.StartsWith(namespaceToUse))
.Where(type => type.BaseType.IsGenericType && type.BaseType.GetGenericTypeDefinition() == typeof(EntityTypeConfiguration<>));
foreach (object configurationInstance in toReg.Select(Activator.CreateInstance))
{
builder.Configurations.Add((dynamic)configurationInstance);
}
}
}
public class IoCExampleDatabaseInitilizer : CreateDatabaseIfNotExists<IoCExampleContext>
{
protected override void Seed(IoCExampleContext context)
{
}
}
public interface IRepository<TEntity> where TEntity : class
{
IQueryable<TEntity> GetQuery();
IEnumerable<TEntity> GetAll();
IEnumerable<TEntity> Where(Expression<Func<TEntity, bool>> predicate);
// ...Various "standard" CRUD calls
}
public class GenericRepository<TEntity> : IRepository<TEntity> where TEntity : class
{
protected DbContext _context;
private readonly DbSet<TEntity> _dbSet;
public GenericRepository(DbContext context)
{
_context = context;
_dbSet = _context.Set<TEntity>();
}
public IQueryable<TEntity> GetQuery()
{
return _dbSet;
}
public IEnumerable<TEntity> GetAll()
{
return GetQuery().AsEnumerable();
}
public IEnumerable<TEntity> Where(Expression<Func<TEntity, bool>> predicate)
{
return GetQuery().Where(predicate);
}
// ...Various "standard" CRUD calls
public void Dispose()
{
OnDispose(true);
}
protected void OnDispose(bool disposing)
{
if (disposing)
{
if (_context != null)
{
_context.Dispose();
_context = null;
}
}
}
}
public class DependencyBootstrapper
{
private ContainerBuilder _builder;
public IContainer Start()
{
_builder = new ContainerBuilder();
_builder.RegisterFilterProvider();
RegisterControllers();
return _builder.Build();
}
private void RegisterControllers()
{
RegisterAssembly(Assembly.GetExecutingAssembly());
_builder.RegisterModelBinderProvider();
RegisterPerLifetimeConnections();
RegisterRepositories();
RegisterServices();
}
private void RegisterAssembly(Assembly assembly)
{
_builder.RegisterModelBinders(assembly);
_builder.RegisterControllers(assembly);
}
private void RegisterRepositories()
{
_builder.RegisterGeneric(typeof(GenericRepository<>)).As(typeof(IRepository<>));
_builder.RegisterType<GenericRepository<SomeObject>>().As<IRepository<SomeObject>>();
//... More registrations
}
private void RegisterServices()
{
_builder.RegisterType<SomeObjectService>().As<ISomeObjectService>();
//... More registrations
}
private void RegisterPerLifetimeConnections()
{
const string connectionStringName = "IoCExample";
_builder.RegisterType<IoCExampleContext>()
.As<DbContext>()
.WithParameter("connectionStringName", connectionStringName)
.InstancePerLifetimeScope();
_builder.Register(c => new HttpContextWrapper(HttpContext.Current))
.As<HttpContextBase>();
}
}
我不知道它是否相关,但由于我们无法访问 global.asax 方法,因此我们通过它调用引导程序PreApplicationStartMethod.OnPreApplicationStart
(据我所知,它与 Application_Start 几乎相同)。
有点令人担忧的是,当我在连接字符串上启用多个活动结果集时,它可以工作——这表明我错误地注册了 DbContext 并且它跨越了多个上下文。
谁能发现我哪里出错了?