Same query of the context - regular and reflection - one succeeds, the other fails. Why?

• 19 Nisan 2012 Perşembe 11:35

   

   
  

  0

  This time it's a puzzling one:

  Here is code basically doing the same thing, one through Reflection and one through normal code (Thema is a custom entity and EntType is a generic type. I am using the Data Service):

  var lst = zenContext.GetType().GetProperty(resourceType.Name).GetValue(DataLoader.zenContext, null) as IEnumerable<EntType>;
  
  var existingZentityObj = (from zoResInst in lst
                            where (zenContext.LoadProperty(zoResInst,"Title").ToString())
                                   .Equals
                                   (entTitle, StringComparison.OrdinalIgnoreCase)
                           select zoResInst).FirstOrDefault();
  var testObj = (from thm in zenContext.Thema
                 where thm.Title.Equals(entTitle, StringComparison.OrdinalIgnoreCase)
                 select thm).FirstOrDefault();

  
  

  The first (existingZentityObj) is null, while the second (testObj) is assigned the correct value (finds a duplicate entity). I have checked that lst above points to the correct collection of objects. Even if I cast it as System.Data.Services.Client.DataServiceQuery<EntType>, then the exception The expression (value(UnityDataImport.ZenDataService.ZentityContext).LoadProperty([10007], "Title").ToString() == "Start Here") is not supported ("Start Here" is simply the value to be compared against. Any ideas? Is this even supported? I believe it is, but when using the DataService it's more difficult, because none of the custom Resources are defined as of base type Resource! Looking forward to your response.

  Cheers,

  WizMan

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