My bad. I misunderstood what you were doing. In order for a Generic to work, the types used must be known at compile-time, not run-time. I've never done what you're trying to do, nor seen it done specifically with EF before, but you may want to look into these[^] possibilities. You'd have to create a method that generates the entire ChangeTracker.Entities() call at runtime. A guide to posting questions on CodeProject Click this: Asking questions is a skill. Seriously, do it. Dave Kreskowiak

Yes, but it appears to be in a different tone than this thread. Time will tell :) Bastard Programmer from Hell :suss: If you can't read my code, try converting it here[^][](X-Clacks-Overhead: GNU Terry Pratchett)

For the Primary key : Public Function Get_PK(ctx As MyEntities, entity As Object) As String Dim objectContext = DirectCast(ctx, System.Data.Entity.Infrastructure.IObjectContextAdapter).ObjectContext Dim t As Type = entity.GetType.BaseType Dim m As MethodInfo = objectContext.GetType().GetMethod("CreateObjectSet", New Type() {}) Dim generic As MethodInfo = m.MakeGenericMethod(t) Dim st As Object = generic.Invoke(objectContext, Nothing) Dim entitySetPI As PropertyInfo = st.GetType().GetProperty("EntitySet") Dim entitySet As Metadata.Edm.EntitySet = DirectCast(entitySetPI.GetValue(st, Nothing), Metadata.Edm.EntitySet) Dim keyNames As IEnumerable(Of String) = entitySet.ElementType.KeyMembers.[Select](Function(k) k.Name) Return keyNames(0) End Function For the Foreign key : Public Function Get_FK(ctx As MyEntities, entity As Object, parenttable As String) As String Dim objectCont = DirectCast(ctx, System.Data.Entity.Infrastructure.IObjectContextAdapter).ObjectContext Dim t As Type = entity.GetType.BaseType Dim m As MethodInfo = objcont.GetType().GetMethod("CreateObjectSet", New Type() {}) Dim generic As MethodInfo = m.MakeGenericMethod(t) Dim st As Object = generic.Invoke(objcont, Nothing) Dim entitySetPI As PropertyInfo = st.GetType().GetProperty("EntitySet") Dim entitySet As Metadata.Edm.EntitySet = DirectCast(entitySetPI.GetValue(st, Nothing), Metadata.Edm.EntitySet) Dim elementtype = entitySet.ElementType Dim entitymember = elementtype.NavigationProperties.Where(Function(t1) t1.ToEndMember.Name = parenttable) Return entitymember.First.GetDependentProperties.First.Name End Function Please give me some reputation , because I found the answer ;P

If mylist IsNot Nothing AndAlso mylist.Count > 0 Then End If ? If the brain were so simple we could understand it, we would be so simple we couldn't. — Lyall Watson

dilkonika wrote: Dim clone = Activator.CreateInstance(entity.GetType()) Yes, that's a simpler solution if you don't need CopyEntity to be generic (that is, if you don't need the static type T for anything else). If you haven't already, you can remove that generic stuff from the declaration of CopyEntity then. dilkonika wrote: Thank you for your help. You're welcome. If the brain were so simple we could understand it, we would be so simple we couldn't. — Lyall Watson

Did you get it to work?

Could be a quirk in EF. Please try this (two lines switched): newitm = New Myobject context.MyObjects.Add(newitm) currentobj.CopyTo(newitm, False) context.savechanges

yes , but when I call the extension , these objects are already loaded in the way that I have described.

That's quite a large question. Personally i would read the relevant system tables from both databases to data tables of a VB program and then compare the rows I have in both data tables. Is there some specific issue you're stuck with?

Sorry - I'm about to head off to the airport and won't get a chance to look at this properly. My advice is to post a question in Quick Answers forum - put in a link to this thread and include the code that you have posted here (you could also post the code I suggested and explain that it didn't work, so everything is in one place). Hopefully someone else will be able to pick it up while I'm away. P.S. - If anyone tells you off for cross-posting point them to this post and I'll take the flack :)

Sorry , but I have posted a code. I have some reasons to not use disable / readonly. Can you give me a solution for my code ? Thank you !

You could do that. If the Click-Event comes from a real click, then e is of type MouseEventArgs. I would recommend using a custom class for two reasons: You can give it a name that explains its purpose so that your code will speak for itself. And if the need would arise to have a third cause for the event you would be out of options when testing if e equals EventArgs.Empty or not.

Alright, nevermind then :) But I have to agree with Richard and Dave - I wouldn't recommend doing that. Wouldn't it be possible to just show all controls at once?

Alternatively; DataGridView With Paging (UserControl)[^]. Bastard Programmer from Hell :suss: If you can't read my code, try converting it here[^][](X-Clacks-Overhead: GNU Terry Pratchett)

You could use theoretically any control you like as all controls have a Click-Event. Buttons or Labels would probably make the most sense. You should create a UserControl that encapsulates all the navigation-related controls. Within that UserControl you should use a FlowLayoutPanel and place the navigation-controls therein. https://msdn.microsoft.com/en-us/library/system.windows.controls.usercontrol%28v=vs.110%29.aspx[^] https://msdn.microsoft.com/en-us/library/system.windows.forms.flowlayoutpanel%28v=vs.110%29.aspx[^] https://www.google.com/search?q=vb.net+winforms+place+controls+runtime&ie=utf-8&oe=utf-8[^]

dilkonika wrote: but I don't want that my application in a such scenario to hang and to be difficult to close it. and of course I want a good messaging behavior to inform the user about what is happening. That is done using a loader, as explained. I've used the principle before, for an app that needed certification and one of the requirements was to ensure that the files were "as expected". It should recognize "any tampering". Easy with a loader and some hashing. dilkonika wrote: About the response , I read somewhere about If you're only interested in a single kind of solution, please add it to the starting-post. If possible, with a hyperlink! Now, since you're not going to change your mind even if I say you cannot guarantee that your backups are not equally corrupted, here's your personalized example; Create a NEW solution, add a console-project Add a class-library and call it "ClassLibrary1". Edit the class in the classlibrary to look like below; namespace ClassLibrary1 { public static class Class1 { public static string Property1 { get { return "Hello From Class1"; } } } } Go to the console-app, and change the Program.cs to below; namespace ConsoleApplication8 { class Program { static void Main(string[] args) { AppDomain.CurrentDomain.AssemblyResolve += currentAppDomain_AssemblyResolve; externalTest(); Console.ReadLine(); } static System.Reflection.Assembly currentAppDomain\_AssemblyResolve(object sender, ResolveEventArgs args) { Console.WriteLine("Assembly Resolve {0}", args.Name); return AppDomain.CurrentDomain.Load(File.ReadAllBytes(@"D:\\Projects\\ConsoleApplication8\\ClassLibrary1\\bin\\Debug\\Copy of ClassLibrary1.dll")); } static void externalTest() { Console.WriteLine(ClassLibrary1.Class1.Property1); } } } Change the path in the above code to your own local folder. Put a reference from the Console-app to ClassLibrary1. Build. Make a copy of the file "ClassLibrary1.dll", rename it to "Copy of ClassLibrary1.dll" (but keep it in that folder, otherwise you'd need to rebuild to update the folder-location in the code) Remove the file "ClassLibrary1.dll" from the debug-folders from BOTH pr

Since I can't see your screen, access your hard-drive, or read your mind, the only information I have available is what you have posted in this thread. Based on that information, there are two possibilities: The filter is active when the form is loaded, which means you are cancelling every message being sent to the form; The filter is not active when the form is loaded, and something else which you haven't shown us is happening on that specific form; If removing the filter fixes the problem, then I'm inclined to think it's #1. However, since you keep insisting that the filter is not active when the form is loaded, then that only leaves #2. Finding the real cause of the problem will involve debugging your code. YOU are the only person who can do that. "These people looked deep within my soul and assigned me a number based on the order in which I joined." - Homer

I already told you why it works. Your first query, and the sub-queries, on the database engine. Getting the SQL query statement from the debugger and examining it in Notepad or in SQL Server Manager would have told you that. Your second query, the last statement in your post, is executed client-side, not on the database engine. I'm not telling you these things, like the above technique, because I like hearing myself type this crap. I tell you these things because this is how I debug and examine the functionality of EF. Have a nice life. A guide to posting questions on CodeProject Click this: Asking questions is a skill. Seriously, do it. Dave Kreskowiak