Hi,

I get an InvalidCastException when I call the ToList() method of a query.

This is the code I'm using where sourceApplicationID is an int.

                LinqMetaData meta = new LinqMetaData(dataAccessAdapter);
                var query = (from r in meta.RedirectRequest
                            where r.OriginalApplicationID == sourceApplicationID
                            select r).IncludeFields(r=> r.ID, r=> r.OriginalApplicationID, r=> r.DestinationApplicationID);

                List<RedirectRequestEntity> redirects = query.ToList();

Stacktrace

[InvalidCastException: Unable to cast object of type 'System.Linq.Expressions.UnaryExpression' to type 'SD.LLBLGen.Pro.LinqSupportClasses.ExpressionClasses.EntityFieldExpression'.]
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleExcludeIncludeFieldsExpression(ExcludeIncludeFieldsExpression expressionToHandle) +208
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.GenericExpressionHandler.HandleExpression(Expression expressionToHandle) +728
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleExpression(Expression expressionToHandle) +110
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.GenericExpressionHandler.HandleSelectExpression(SelectExpression expressionToHandle, SelectExpression newInstance) +239
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.GenericExpressionHandler.HandleSelectExpression(SelectExpression expressionToHandle) +111
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleSelectExpression(SelectExpression expressionToHandle) +98
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.GenericExpressionHandler.HandleExpression(Expression expressionToHandle) +1514
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleExpression(Expression expressionToHandle) +110
   SD.LLBLGen.Pro.LinqSupportClasses.LLBLGenProProviderBase.HandleExpressionTree(Expression expression) +848
   SD.LLBLGen.Pro.LinqSupportClasses.LLBLGenProProviderBase.Execute(Expression expression) +33
   SD.LLBLGen.Pro.LinqSupportClasses.LLBLGenProProviderBase.System.Linq.IQueryProvider.Execute(Expression expression) +29
   SD.LLBLGen.Pro.LinqSupportClasses.LLBLGenProQuery`1.Execute() +32
   SD.LLBLGen.Pro.LinqSupportClasses.LLBLGenProQuery`1.System.Collections.Generic.IEnumerable<T>.GetEnumerator() +53
   System.Collections.Generic.List`1..ctor(IEnumerable`1 collection) +369
   System.Linq.Enumerable.ToList(IEnumerable`1 source) +54
   Orangehill.Cal.BusinessLogic.LinqSO.GetRedirectsViaLinq2(Int32 sourceApplicationID) in C:\Projects\CAL\Linq2LLBLGen\Solution\Orangehill.Cal.BusinessLogic\LinqSO.cs:43
   Orangehill.Cal.Backend.Login.OnInit(EventArgs e) in C:\Projects\CAL\Linq2LLBLGen\Solution\Orangehill.Cal.Backend\public\Login.aspx.cs:38
   System.Web.UI.Control.InitRecursive(Control namingContainer) +321
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +834

Any suggestions?

T.i.a. Arjan Vermunt

Is any of these fields specified in the includefields call a nullable type?

No, they are all integer fields. The ID field is an identity field.

arjanv wrote:

No, they are all integer fields. The ID field is an identity field.

Yes, but a nullable<int> or not? (i.e. are they nullable in the DB) ?

All fields of the table are not nullable

arjanv wrote:

All fields of the table are not nullable

Ok thanks

Still weird where the unary comes from though. Could you enable tracing on the linq provider? (at level 3 !) ? You'll then get the expression as it is fed to the linq provider in text. Could you paste it here please?

Hope this is what you asked for. I used this value in de config file.

<add name="LinqExpressionHandler" value="3"/>

output

: Initial expression to process:
value(SD.LLBLGen.Pro.LinqSupportClasses.DataSource2`1[Orangehill.Cal.LLBL.EntityClasses.RedirectRequestEntity]).Where(r => (r.OriginalApplicationID = value(Orangehill.Cal.BusinessLogic.LinqSO+<>c__DisplayClass2).sourceApplicationID)).ExcludeFields( value(System.Linq.Expressions.Expression`1[System.Func`2[ Orangehill.Cal.LLBL.EntityClasses.RedirectRequestEntity,System.Object]][]))
A first chance exception of type 'System.InvalidCastException' occurred in SD.LLBLGen.Pro.LinqSupportClasses.NET35.DLL

Yes that's what I was looking for It would reveal if there were unexpected unaryexpressions somewhere, which isn't the case. so I've to look elsewhere

Do you need something from me, generated code or the project file? if so, I would prefer to send it via email, because it's a spin off from a live application.

arjanv wrote:

Do you need something from me, generated code or the project file? if so, I would prefer to send it via email, because it's a spin off from a live application.

If you could re-create the error in a northwind based query it would be great (you can just post the query here). I haven't tried reproducing it yet, I'll try on monday (with the other issue still open, the prefetch path error).

If you could re-create the error in a northwind based query it would be great

Does it really has to be reproducable against the northwind database? A database connection isn't necessary, because it's not getting there.

Found out what causes the Exception .

Tables containing bit fields cause the exception to occur. I reproduced it on the Products table of the Northwind database.

arjanv wrote:

Found out what causes the Exception .

Tables containing bit fields cause the exception to occur. I reproduced it on the Products table of the Northwind database.

as in: excluding 'Discontinued' or including 'Discontinued' caused it? That would explain why our unittests work but you ran into this issue: we don't use a bitfield in these tests.

No, as in: when the entity contains a bit field

Sorry, spoke too soon. had it working for employee's added products entity and got the Unary cast exception. Concluded too soon. I attach a test case against the northwind database.

I can repro it when I add a bitfield to the IncludeFields list:

[Test]
public void GetAllProductsWithJustAFewFieldsIncluded()
{
    using(DataAccessAdapter adapter = new DataAccessAdapter())
    {
        LinqMetaData metaData = new LinqMetaData(adapter);
        var q = (from p in metaData.Product
                 select p).IncludeFields(p => p.ProductName, p => p.QuantityPerUnit, p=>p.Discontinued);

        int count = 0;
        foreach(var v in q)
        {
            count++;
            Assert.IsFalse(v.ReorderLevel.HasValue);
            Assert.IsTrue(v.ProductName.Length > 0);
            Assert.IsTrue(v.QuantityPerUnit.Length > 0);
        }
        Assert.AreEqual(77, count);
    }
}

When I remove p=>p.Discontinued from the IncludeFields() call, the query works fine (on the latest codebase). Looking into it

Including or excluding value types are the problem. Try adding an int field in the excluding list. The same result.

It happens with any entity field which is of a valuetype (e.g. int, bool, etc.). -> an extra convert is added by the C#/VB.NET compiler to convert the field expression to the 'object' type.

(edit) heh, I didn't saw your previous post

Fixed in next build!