Asp.net mvc 错误:确保控制器具有无参数公共构造函数webapi
我正在使用webapi、unity和mvc。我得到的错误是“确保控制器有一个无参数的公共构造函数”。我见过类似的问题,但仍然无法使其发挥作用。我已经安装了unity.webapi,似乎有所有必要的参考资料:Asp.net mvc 错误:确保控制器具有无参数公共构造函数webapi,asp.net-mvc,parameters,controller,unity-container,asp.net-web-api2,Asp.net Mvc,Parameters,Controller,Unity Container,Asp.net Web Api2,我正在使用webapi、unity和mvc。我得到的错误是“确保控制器有一个无参数的公共构造函数”。我见过类似的问题,但仍然无法使其发挥作用。我已经安装了unity.webapi,似乎有所有必要的参考资料: Microsoft.Practices.Unity-运行时:v4.0.30319,版本:3.5.0.0 Microsoft.Practices.Unity.Mvc-运行时:v4.0.30319,版本:3.5.0.0 Unity.WebApi-运行时:v4.0.30319,版本:5.1.0.
- Microsoft.Practices.Unity-运行时:v4.0.30319,版本:3.5.0.0
- Microsoft.Practices.Unity.Mvc-运行时:v4.0.30319,版本:3.5.0.0
- Unity.WebApi-运行时:v4.0.30319,版本:5.1.0.0
- System.Web.Http-运行时:v4.0.30319,版本:5.2.2.0
- System.Web.Mvc-运行时:v4.0.30319,版本:5.2.2.0
public static class Bootstrapper
{
public static IUnityContainer Initialise()
{
var container = BuildUnityContainer();
DependencyResolver.SetResolver(new UnityDependencyResolver(container));
return container;
}
private static IUnityContainer BuildUnityContainer()
{
var container = new UnityContainer();
container.RegisterType<IDatabaseFactoryHouseDB, DatabaseFactoryHouseDB>(new HierarchicalLifetimeManager());
container.RegisterType<UnitOfWorkHouseDB>();
// repositories
container.RegisterType<IEmployeeRepository, EmployeeRepository>();
// services
container.RegisterType<IEmployeeService, EmployeeService>();
RegisterTypes(container);
return container;
}
public static void RegisterTypes(IUnityContainer container) { }
}
WebApiConfig:
public static void Register(HttpConfiguration config)
{
config.MapHttpAttributeRoutes();
config.Routes.MapHttpRoute(
name: "DefaultApi",
routeTemplate: "api/{controller}/{id}",
defaults: new { id = RouteParameter.Optional }
);
// use json strings as the default return value for the app
config.Formatters.JsonFormatter.SupportedMediaTypes.Add(new MediaTypeHeaderValue("text/html"));
// Uncomment the following line of code to enable query support for actions with an IQueryable or IQueryable<T> return type.
// To avoid processing unexpected or malicious queries, use the validation settings on QueryableAttribute to validate incoming queries.
// For more information, visit http://go.microsoft.com/fwlink/?LinkId=279712.
//config.EnableQuerySupport();
// To disable tracing in your application, please comment out or remove the following line of code
// For more information, refer to: http://www.asp.net/web-api
config.EnableSystemDiagnosticsTracing();
}
不知道我错过了什么
编辑:我注意到我的App\u Start文件夹中有一个UnityConfig类。在查看了Sarathy的评论后,我意识到它不应该被称为。我在global.asax中注释掉了我的引导程序初始化,并添加了UnityConfig.RegisterComponents()行,因此现在我的global.asax如下所示:
public class WebApiApplication : System.Web.HttpApplication
{
protected void Application_Start()
{
UnityConfig.RegisterComponents(); // <--- added
AreaRegistration.RegisterAllAreas();
GlobalConfiguration.Configure(WebApiConfig.Register);
FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
RouteConfig.RegisterRoutes(RouteTable.Routes);
BundleConfig.RegisterBundles(BundleTable.Bundles);
Database.SetInitializer<HouseDBContext>(null);
//Bootstrapper.Initialise(); <-- not using bootstrapper anymore
//required for setting routes in the attributes of a controller method
GlobalConfiguration.Configuration.EnsureInitialized();
}
}
public static class UnityConfig
{
public static void RegisterComponents()
{
var container = new UnityContainer();
// register all your components with the container here
// it is NOT necessary to register your controllers
// e.g. container.RegisterType<ITestService, TestService>();
container.RegisterType<IDatabaseFactoryHouseDB, DatabaseFactoryHouseDB>(new HierarchicalLifetimeManager());
//container.RegisterType<IUnitOfWork>();
container.RegisterType<UnitOfWorkHouseDB>();
// repositories
container.RegisterType<IEmployeeRepository, EmployeeRepository>();
// services
container.RegisterType<IEmployeeService, EmployeeService>();
GlobalConfiguration.Configuration.DependencyResolver = new Unity.WebApi.UnityDependencyResolver(container);
}
}
我在使用unityconfig方法时仍然会遇到错误。使用bootstrapper,我没有得到错误,但我的服务没有初始化
我完全糊涂了。不知怎的,我觉得我混合了MVC和WebApi,事情没有正确解决
编辑2:
我查看了无参数构造函数错误的内部异常,注意到它提到了我的IUnitOfWork类:
依赖项解析失败,请键入=
\“AngularMVC.Controllers.EmployeeApiController\”,名称=
\“(无)\”\r\n在解析时发生异常。\r\n异常
是:InvalidOperationException-当前类型,
AngularMVC.Models.Interfaces.IUnitOfWork是一个接口,不能
要构造。是否缺少类型
映射?\r\n--------------------------------------------\r\n在
发生异常时,容器为:\r\n\r\n
AngularMVC.Controllers.EmployeeApiController,(无)\r\n
构造函数的参数“employeeService”
AngularMVC.Controllers.EmployeeApiController(AngularMVC.Services.IEEmployeeService
employeeService)\r\n正在解析
AngularMVC.Services.EmployeeService,(无)(映射自
AngularMVC.Services.IEEmployeeService,(无))\r\n
构造函数的参数“unitOfWork”
AngularMVC.Services.EmployeeService(AngularMVC.Models.Repositories.IEEmployeeRepository
employeeRepository,AngularMVC.Models.Interfaces.IUnitOfWork
unitOfWork)\r\n正在解析
AngularMVC.Models.Interfaces.IUnitOfWork,(无)\r\n“
这只是:
public interface IUnitOfWork
{
void Commit();
}
当我在UnityConfig中执行以下操作时:
public static class UnityConfig
{
public static void RegisterComponents()
{
var container = new UnityContainer();
GlobalConfiguration.Configuration.DependencyResolver = new UnityDependencyResolver(container);
}
}
container.RegisterType<IUnitOfWork>();
IUnitOfWork sm = container.Resolve<IUnitOfWork>();
container.RegisterType();
IUnitOfWork sm=container.Resolve();
我收到了相同的错误,指出“当前类型AngularMVC.Models.Interfaces.IUnitOfWork是一个接口,无法构造。是否缺少类型映射?”从代码中,我可以看出您正在使用Unity作为IoC容器。IoC容器将处理控制器类的初始化 要使IoC容器创建控制器的实例,控制器类需要具有无参数公共构造函数(也称为默认构造函数) 更新1:2015年2月18日 从您的代码中,我还没有看到IUnitOfWork接口的实现。工作单元是在领域中心建模中广泛使用的模式。通常,工作单元模式与存储库模式一起使用。工作单元的目的是使多个存储库可以在同一数据库上下文上工作 从你的代码,你注册
//container.RegisterType<IUnitOfWork>();
container.RegisterType<UnitOfWorkHouseDB>();
i工作实施:
public class UnitOfWork : IUnitOfWork
{
//DBContext could your own db context, or a interface, like IDatabaseFactoryHouseDB
private DBContext _ctx;
public UnitOfWork(DbContext ctx)
{
_ctx = ctx;
}
private IEmployeeRepository _EmployeeRepository;
public IEmployeeRepository EmployeeRepository
{
get { return _EmployeeRepository ?? (_EmployeeRepository = new EmployeeRepository(_ctx)); }
}
private ICustomerRepository _CustomerRepository;
public ICustomerRepository CustomerRepository
{
get { return _CustomerRepository ?? (_CustomerRepository = new CustomerRepository(_ctx)); }
}
public void Commit()
{
_ctx.SaveChange();
}
}
您是否在任何地方使用UnityConfig.RegisterComponents()?您是否应该使用GlobalConfiguration.Configuration.DependencyResolver中的容器集注册依赖项,并从WebApiConfig.Register()使用它?我的App_Start文件夹中有一个名为UnityConfig的类没有被调用。我在其中注册了服务,在global.asax中注释掉了bootstrapper初始化,并添加了UnityConfig.RegisterComponents(),但仍然得到了无参数构造函数错误。我觉得我把Unity与MVC控制器和webapi的使用弄错了,因为所有这些在MVC中都能很好地工作;萨拉西——多亏了你和杰夫,我才意识到我的错误。首先,我没有在我的工作单元中实现IUnitOfWork。DOH!你完全正确!我发现我的UnitOfWork类没有实现IUnitOfWork。难怪它让我感到不适。我不知道我怎么会错过。再次感谢!
container.RegisterType<IUnitOfWork>();
IUnitOfWork sm = container.Resolve<IUnitOfWork>();
public class EmployeeApiController : ApiController
{
private readonly IEmployeeService employeeService;
public EmployeeAPIController() : base()
{
}
public EmployeeApiController(IEmployeeService employeeService)
{
this.employeeService = employeeService;
}
}
//container.RegisterType<IUnitOfWork>();
container.RegisterType<UnitOfWorkHouseDB>();
container.RegisterType<IUnitOfWork, UnitOfWorkHouseDB>();
// repositories
container.RegisterType<IEmployeeRepository, EmployeeRepository>();
public interface IUnitOfWork
{
void Commit();
}
public class UnitOfWork : IUnitOfWork
{
//DBContext could your own db context, or a interface, like IDatabaseFactoryHouseDB
private DBContext _ctx;
public UnitOfWork(DbContext ctx)
{
_ctx = ctx;
}
private IEmployeeRepository _EmployeeRepository;
public IEmployeeRepository EmployeeRepository
{
get { return _EmployeeRepository ?? (_EmployeeRepository = new EmployeeRepository(_ctx)); }
}
private ICustomerRepository _CustomerRepository;
public ICustomerRepository CustomerRepository
{
get { return _CustomerRepository ?? (_CustomerRepository = new CustomerRepository(_ctx)); }
}
public void Commit()
{
_ctx.SaveChange();
}
}