我最近一直在使用带有StructureMap的新MVC框架并且总体上已经取得了很好的结果,但是,我一直遇到一个我无法理解的奇怪错误或者弄清楚如何解决.
这是我的架构：
> DBContext – linqTosql数据上下文.
> IRepository – 定义数据方法的合同.
> IService – 定义服务方法的合同.
>控制器 – 本例中为两个.
因此我有：
public class Repo : IRepository
{
public Repo(DBContext db)
{
.....
}
}
public class Service : IService
{
public Service(IRepository repo)
{
.....
}
}
public class ControllerOne : Controller
{
public ControllerOne(IService service)
{
.....
}
}
public class ControllerTwo : Controller
{
public ControllerTwo(IService service)
{
.....
}
}
StructureMap用于定义IRepository和IService的具体类型,DBContext由lamba表达式构成 – ()=>由DSL注册表配置的新DBContext().
目前没有DBContext的缓存
在问题上：
我的索引页面加载并同时向ControllerOne和ControllerTwo发出两个Ajax请求,这些请求是通过MvcContrib的StructureMap控制器工厂构建的.
StructureMap注入了IService的具体类型,而IService又是使用配置的IRepository实例和新的DBContext对象创建的.
ControllerOne正在从IService实例请求一个模型,然后将其作为JsonActionResult返回,该模型由Newtonsoft.Json呈现.
ControllerTwo从IService实例请求一个不同的模型,当MVC框架执行ActionResult时,它也被序列化为Json对象.
我在VS2008中通过Cassini运行网站.
>数据无法读取,已有读者打开或
>无法将数据加载到数据表中,因为数据已存在(我目前没有确切的例外情况,但两者都是LinqTosql的内部).
如果ControllerOne中发生错误,则ControllerTwo也会因类似错误而失败,就好像这两个请求正在运行共享对象一样.
它不会一直出错,但它足以让我关注我的架构,并且它在某种程度上配置错误.
有没有什么方法可以在后续请求中返回ControllerOne和ControllerTwo的相同实例,或者它是否以任何方式缓存DBContext？即使我不是要求它？
在Visual Studio / Cassini中工作时有没有人见过类似的东西？通过IIS有帮助吗？
关闭Visual Studio并再次打开通常可以解决问题一段时间.
非常感谢,如果有人能够解决这个问题.
编辑：包括来自NLog日志文件的日志片段(线程ID是半冒号前的数字)：
03/20/2009 01:40:32 12: controller=Timesheet,date=2001-05-06,Action=WeekEnding /beta/Timesheet/2001-05-06?_dc=1237513232397 03/20/2009 01:40:32 10: controller=Timesheet,Action=WeekEnding /beta/Timesheet/2001-05-06?_dc=1237513232449 03/20/2009 01:40:32 10: There is already an open DataReader associated with this Command which must be closed first. System.InvalidOperationException[br] at System.Data.sqlClient.sqlInternalConnectionTds.ValidateConnectionForExecute(sqlCommand command) at System.Data.sqlClient.sqlConnection.ValidateConnectionForExecute(String method,sqlCommand command) at System.Data.sqlClient.sqlCommand.ValidateCommand(String method,Boolean async) at System.Data.sqlClient.sqlCommand.RunExecuteReader(CommandBehavior cmdBehavior,RunBehavior runBehavior,Boolean returnStream,String method,DbAsyncResult result) at System.Data.sqlClient.sqlCommand.RunExecuteReader(CommandBehavior cmdBehavior,String method) at System.Data.sqlClient.sqlCommand.ExecuteReader(CommandBehavior behavior,String method) at System.Data.sqlClient.sqlCommand.ExecuteDbDataReader(CommandBehavior behavior) at System.Data.Common.DbCommand.ExecuteReader() at System.Data.Linq.sqlClient.sqlProvider.Execute(Expression query,QueryInfo queryInfo,IObjectReaderFactory factory,Object[] parentArgs,Object[] userArgs,ICompiledSubQuery[] subQueries,Object lastResult) at System.Data.Linq.sqlClient.sqlProvider.ExecuteAll(Expression query,QueryInfo[] queryInfos,Object[] userArguments,ICompiledSubQuery[] subQueries) at System.Data.Linq.sqlClient.sqlProvider.System.Data.Linq.Provider.IProvider.Execute(Expression query) at System.Data.Linq.DataQuery`1.System.Linq.IQueryProvider.Execute[S](Expression expression) at System.Linq.Queryable.Sum[TSource](IQueryable`1 source,Expression`1 selector) at HCD.Intranet.Core.Data.Linq.LinqEmployeeRepository.CalculateHolidaysRemaining(Employee employee,DateTime weekEnding,Int32 nonProjectId) at HCD.Intranet.Core.Services.Impl.EmployeeService.CalculateHolidaysRemaining(Employee employee,DateTime weekEnding) at HCD.Intranet.Core.Models.Timesheet.CalculateHolidaysRemaining() at HCD.Intranet.Core.Models.Json.TimesheetJsonConverter.WriteTimesheet(JsonWriter writer,Timesheet timesheet) at HCD.Intranet.Core.Models.Json.TimesheetJsonConverter.WriteJson(JsonWriter writer,Object value) at Newtonsoft.Json.JsonSerializer.SerializeValue(JsonWriter writer,Object value,JsonConverter memberConverter) at Newtonsoft.Json.JsonSerializer.WriteMemberInfoProperty(JsonWriter writer,JsonMemberMapping memberMapping) at Newtonsoft.Json.JsonSerializer.SerializeObject(JsonWriter writer,JsonConverter memberConverter) at Newtonsoft.Json.JsonSerializer.Serialize(JsonWriter jsonWriter,Object value) at HCD.Intranet.Core.Web.Mvc.NewtonsoftJsonResult.ExecuteResult(ControllerContext context) at System.Web.Mvc.ControllerActionInvoker.InvokeActionResult(ControllerContext controllerContext,ActionResult actionResult) at System.Web.Mvc.ControllerActionInvoker.<>c__DisplayClass11.<InvokeActionResultWithFilters>b__e() at System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter,ResultExecutingContext preContext,Func`1 continuation) at System.Web.Mvc.ControllerActionInvoker.<>c__DisplayClass11.<>c__DisplayClass13.<InvokeActionResultWithFilters>b__10() at System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter,Func`1 continuation) at System.Web.Mvc.ControllerActionInvoker.<>c__DisplayClass11.<>c__DisplayClass13.<InvokeActionResultWithFilters>b__10() at System.Web.Mvc.ControllerActionInvoker.InvokeActionResultWithFilters(ControllerContext controllerContext,IList`1 filters,ActionResult actionResult) at System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext,String actionName) 03/20/2009 01:40:32 12: Invalid attempt to call Read when reader is closed. System.InvalidOperationException[br] at System.Data.Linq.sqlClient.sqlProvider.Execute(Expression query,String actionName) 03/20/2009 01:41:58 12: controller=Timesheet,month=6,year=2001,Action=Calendar /beta/Timesheet/Calendar/6/2001?_dc=1237513318470 03/20/2009 01:41:59 10: controller=Timesheet,date=2001-06-03,Action=WeekEnding /beta/Timesheet/2001-06-03?_dc=1237513318509 03/20/2009 01:41:59 12: The null value cannot be assigned to a member with type System.Int32 which is a non-nullable value type. System.InvalidOperationException[br] at Read_TimesheetEntry(ObjectMaterializer`1 ) at System.Data.Linq.sqlClient.ObjectReaderCompiler.ObjectReader`2.MoveNext() at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source) at HCD.Intranet.Core.Data.Linq.LinqTimesheetRepository.GetEntries(Int32 timesheetHeaderId) at HCD.Intranet.Core.Services.Impl.TimesheetService.GetEntries(Int32 timesheetHeaderId) at HCD.Intranet.Core.Models.Timesheet.get_InnerEntries() at HCD.Intranet.Core.Models.TimeMap..ctor(Timesheet timesheet) at HCD.Intranet.Core.Models.Json.TimesheetCalendarJsonConverter.WriteTimesheet(JsonWriter writer,Timesheet[] timesheets) at HCD.Intranet.Core.Models.Json.TimesheetCalendarJsonConverter.WriteJson(JsonWriter writer,String actionName) 03/20/2009 01:41:59 12: controller=Timesheet,Action=WeekEnding /beta/Timesheet/2001-06-03?_dc=1237513318545 03/20/2009 01:41:59 12: There is already an open DataReader associated with this Command which must be closed first. System.InvalidOperationException[br] at System.Data.sqlClient.sqlInternalConnectionTds.ValidateConnectionForExecute(sqlCommand command) at System.Data.sqlClient.sqlConnection.ValidateConnectionForExecute(String method,String actionName) 03/20/2009 01:41:59 10: Invalid attempt to call Read when reader is closed. System.InvalidOperationException[br] at System.Data.Linq.sqlClient.sqlProvider.Execute(Expression query,String actionName)
