我在一些Silverlight組件的ASP.Net應用程序中使用.Net RIA Services的七月CTP。我從Silverlight調用RIA服務。.Net RIA服務:DomainService需要一個無參數構造函數?
當我嘗試在我的域服務(LinqToEntitiesDomainService對象)中使用Unity和構造函數依賴項注入時,出現了我的問題。 Silverlight應用程序現在抱怨沒有無參數的構造函數。
我不想有無參數的構造函數,我想要Unity來解析構造函數參數。這可能嗎?難道我做錯了什麼?或者我應該找到另一種方法來注入我的構造函數參數?
public class DashboardService : LinqToEntitiesDomainService<DashboardEntities>
{
private IUserService userService;
public DashboardService(IUserService userService)
: base()
{
if (userService == null)
{
throw ExceptionBuilder.ArgumentNull("userService");
}
this.userService = userService;
}
...
這裏是我得到的錯誤:
Webpage error details
User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.04506.648; .NET CLR 3.5.21022; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)
Timestamp: Tue, 18 Aug 2009 14:34:54 UTC
Message: Unhandled Error in Silverlight 2 Application No parameterless constructor defined for this object. at System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandle& ctor, Boolean& bNeedSecurityCheck)
at System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean fillCache)
at System.RuntimeType.CreateInstanceImpl(Boolean publicOnly, Boolean skipVisibilityChecks, Boolean fillCache)
at System.Activator.CreateInstance(Type type, Boolean nonPublic)
at System.Web.DomainServices.DomainService.DefaultDomainServiceFactory.CreateDomainService(Type domainServiceType, DomainServiceContext context)
at System.Web.Ria.DataServiceFactory.GetDataService(HttpContext context)
at System.Web.Ria.DataServiceFactory.System.Web.IHttpHandlerFactory.GetHandler(HttpContext context, String requestType, String url, String pathTranslated)
Line: 1
Char: 1
Code: 0
URI: http://dev.localhost/Home
我一直在尋找它。感謝那 :) – Davita 2011-04-21 11:44:00