我是EF + MVC的新手，请指教
无法创建“System.Object”类型的常量值。在此上下文中仅支持基元类型或枚举类型。
我已经附加了存储库，控制器，视图和错误堆栈跟踪中的代码。
PeopleOnSite
public class PeopleOnSite
{
public string DoorName { get; set; }
public int InductionNumber { get; set; }
public string PersonName { get; set; }
public string Contractor { get; set; }
public string Trade { get; set; }
public DateTime? TimeIn { get; set; }
public int? HoursOnSite { get; set; }
}
回购
public List<PeopleOnSite> GetRollCall()
{
var query = (from a in context.AccessLog
join ad in context.AccessDetailLog on a.EventID equals ad.AccessID
join d in context.Doors on ad.ZoneID equals d.ZoneID
join p in context.People on a.PersonID equals p.PersonID
join w in context.Workers on p.PersonID equals w.PersonID
join c in context.Contractors on w.ContractorID equals c.ContractorID
join t in context.Trades on w.TradeID equals t.TradeID
orderby a.FirstTimeIn
select new PeopleOnSite
{
DoorName = d.DoorName,
InductionNumber = p.InductionNumber,
// for anyone else that stumbles here it should be + " " +
PersonName = p.FirstName + ' ' + p.LastName,
Contractor = c.CompanyName,
Trade = t.Name,
TimeIn = a.FirstTimeIn,
HoursOnSite = 10
});
return query.ToList();
}
控制器
List<PeopleOnSite> peopleOnSite = taRepo.GetRollCall();
查看
@foreach (var item in Model.PeopleOnSite)
{
<tr>
<td>
@Html.DisplayFor(modelItem => item.DoorName)
</td>
<td>@Html.DisplayFor(modelItem => item.InductionNumber)</td>
<td>@Html.DisplayFor(modelItem => item.PersonName)</td>
<td>@Html.DisplayFor(modelItem => item.Contractor)</td>
<td>@Html.DisplayFor(modelItem => item.Trade)</td>
<td class="text-center">@Html.DisplayFor(modelItem => item.TimeIn)</td>
<td class="text-center">@Html.DisplayFor(modelItem => item.HoursOnSite)</td>
</tr>
}
错误
Server Error in '/' Application.
Unable to create a constant value of type 'System.Object'. Only primitive types or enumeration types are supported in this context.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.NotSupportedException: Unable to create a constant value of type 'System.Object'. Only primitive types or enumeration types are supported in this context.
Source Error:
Line 74: HoursOnSite = 10
Line 75: });
Line 76: return query.ToList();
Line 77:
Line 78: //var query = GetRollCall().Select( a => a.PersonName, context.People )
Source File: d:\SiteSentryWeb\SiteSentry.Data\ModelsAndRepositories\TimeAttendanceRepository.cs Line: 76
Stack Trace:
[NotSupportedException: Unable to create a constant value of type 'System.Object'. Only primitive types or enumeration types are supported in this context.]
System.Data.Entity.Core.Objects.ELinq.ConstantTranslator.TypedTranslate(ExpressionConverter parent, ConstantExpression linq) +1484
System.Data.Entity.Core.Objects.ELinq.TypedTranslator`1.Translate(ExpressionConverter parent, Expression linq) +88
System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateExpression(Expression linq) +149
System.Data.Entity.Core.Objects.ELinq.BinaryTranslator.TypedTranslate(ExpressionConverter parent, BinaryExpression linq) +122
System.Data.Entity.Core.Objects.ELinq.TypedTranslator`1.Translate(ExpressionConverter parent, Expression linq) +88
System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateExpression(Expression linq) +149
System.Data.Entity.Core.Objects.ELinq.BinaryTranslator.TypedTranslate(ExpressionConverter parent, BinaryExpression linq) +87
System.Data.Entity.Core.Objects.ELinq.TypedTranslator`1.Translate(ExpressionConverter parent, Expression linq) +88
System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateExpression(Expression linq) +149
System.Data.Entity.Core.Objects.ELinq.MemberInitTranslator.TypedTranslate(ExpressionConverter parent, MemberInitExpression linq) +724
System.Data.Entity.Core.Objects.ELinq.TypedTranslator`1.Translate(ExpressionConverter parent, Expression linq) +88
System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateExpression(Expression linq) +149
System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateLambda(LambdaExpression lambda, DbExpression input) +168
System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateLambda(LambdaExpression lambda, DbExpression input, DbExpressionBinding& binding) +159
System.Data.Entity.Core.Objects.ELinq.OneLambdaTranslator.Translate(ExpressionConverter parent, MethodCallExpression call, DbExpression& source, DbExpressionBinding& sourceBinding, DbExpression& lambda) +166
System.Data.Entity.Core.Objects.ELinq.SelectTranslator.Translate(ExpressionConverter parent, MethodCallExpression call) +71
System.Data.Entity.Core.Objects.ELinq.SequenceMethodTranslator.Translate(ExpressionConverter parent, MethodCallExpression call, SequenceMethod sequenceMethod) +47
System.Data.Entity.Core.Objects.ELinq.MethodCallTranslator.TypedTranslate(ExpressionConverter parent, MethodCallExpression linq) +141
System.Data.Entity.Core.Objects.ELinq.TypedTranslator`1.Translate(ExpressionConverter parent, Expression linq) +88
System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.TranslateExpression(Expression linq) +149
System.Data.Entity.Core.Objects.ELinq.ExpressionConverter.Convert() +50
System.Data.Entity.Core.Objects.ELinq.ELinqQueryState.GetExecutionPlan(Nullable`1 forMergeOption) +563
System.Data.Entity.Core.Objects.<>c__DisplayClassb.<GetResults>b__a() +83
System.Data.Entity.Core.Objects.ObjectContext.ExecuteInTransaction(Func`1 func, IDbExecutionStrategy executionStrategy, Boolean startLocalTransaction, Boolean releaseConnectionOnSuccess) +444
System.Data.Entity.Core.Objects.<>c__DisplayClassb.<GetResults>b__9() +270
System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute(Func`1 operation) +251
System.Data.Entity.Core.Objects.ObjectQuery`1.GetResults(Nullable`1 forMergeOption) +645
System.Data.Entity.Core.Objects.ObjectQuery`1.<System.Collections.Generic.IEnumerable<T>.GetEnumerator>b__0() +84
System.Lazy`1.CreateValue() +416
System.Lazy`1.LazyInitValue() +152
System.Lazy`1.get_Value() +75
System.Data.Entity.Internal.LazyEnumerator`1.MoveNext() +40
System.Collections.Generic.List`1..ctor(IEnumerable`1 collection) +381
System.Linq.Enumerable.ToList(IEnumerable`1 source) +58
SiteSentry.Data.ModelsAndRepositories.TimeAttendanceRepository.GetRollCall() in d:\SiteSentryWeb\SiteSentry.Data\ModelsAndRepositories\TimeAttendanceRepository.cs:76
SiteSentry.WebMvc.Areas.SiteSentry.Controllers.SiteController.Index() in d:\SiteSentryWeb\SiteSentry.WebMvc\Areas\SiteSentry\Controllers\SiteController.cs:53
lambda_method(Closure , ControllerBase , Object[] ) +101
System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters) +59
System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) +434
System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +60
System.Web.Mvc.Async.ActionInvocation.InvokeSynchronousActionMethod() +76
System.Web.Mvc.Async.AsyncControllerActionInvoker.<BeginInvokeSynchronousActionMethod>b__39(IAsyncResult asyncResult, ActionInvocation innerInvokeState) +36
System.Web.Mvc.Async.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult) +73
System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +136
System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +102
System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +49
System.Web.Mvc.Async.AsyncInvocationWithFilters.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3f() +117
System.Web.Mvc.Async.<>c__DisplayClass48.<InvokeActionMethodFilterAsynchronouslyRecursive>b__41() +323
System.Web.Mvc.Async.<>c__DisplayClass33.<BeginInvokeActionMethodWithFilters>b__32(IAsyncResult asyncResult) +44
System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +47
System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +136
System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +102
System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +50
System.Web.Mvc.Async.<>c__DisplayClass2b.<BeginInvokeAction>b__1c() +72
System.Web.Mvc.Async.<>c__DisplayClass21.<BeginInvokeAction>b__1e(IAsyncResult asyncResult) +185
System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +42
System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +133
System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +56
System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +40
System.Web.Mvc.Controller.<BeginExecuteCore>b__1d(IAsyncResult asyncResult, ExecuteCoreState innerState) +34
System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +70
System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +139
System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +59
System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +40
System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +44
System.Web.Mvc.Controller.<BeginExecute>b__15(IAsyncResult asyncResult, Controller controller) +39
System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +62
System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +139
System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +59
System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +40
System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +39
System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.EndExecute(IAsyncResult asyncResult) +39
System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__5(IAsyncResult asyncResult, ProcessRequestState innerState) +39
System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +70
System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +139
System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +59
System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +40
System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +40
System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +38
System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +9688704
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155