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SfDatagrid - Entity Framework "adding row" issue

Hi,

I've got a SfDataGrid which is data bound to an ObservableCollection of Entity Framework items.

When I add a new row and load the Entity Framework items again* an error message pops up:

Message=Das Objekt des Typs "DataLayer.EntitiesDB.SequenceEditorItem" kann nicht in Typ "System.Data.Entity.DynamicProxies.SequenceEditorItem_5090EDC7CFDC945E13DBDF0872CAB31598B97FE519E86F7BE4466D584C2402D6" umgewandelt werden.  HResult=-2147467262System.InvalidCastException was unhandled 

* Database.Hardware.Load();
hardwareViewSource.Source = Database.Hardware.Local;

Using the common MS DataGrid this does not happen. Furthermore Database.SaveChanges() does not solve the problem. What can be the reason for this?

I'm using VS2015, .NET4.6.1, EF6.1.3


2 Replies

JZ Jonas Züger September 9, 2016 12:09 PM UTC

Addendum:

After first investigation it seems that the SfDataGrid creates a "normal" object whereas the MS Datagrid creates an Entity Framework proxy item. Loading this back to the SfDataGrid causes an InvalidCastException.

Now my question is a more concrete: Is it possible to tell SfDataGrid to create a proxy item by the built in "add row" function?



JG Jai Ganesh S Syncfusion Team September 12, 2016 12:47 PM UTC

Hi Züger, 
 
We have analyzed your query. You can achieve your requirement to add a new row in SfDataGrid when using EntityFrameworkCollection by wiring the AddNewRowInitiating event and save the changes like below, 
 
this.datagrid.AddNewRowInitiating += datagrid_AddNewRowInitiating;

 
void datagrid_AddNewRowInitiating(object sender, AddNewRowInitiatingEventArgs args)         
{ 
            Category newRecord = args.NewObject as Category; 
            Category category = new Category(); 
            category.Description = newRecord.Description; 
            using(Entities entity=new Entities()) 
            { 
                entity.Categories.Add(category); 
                entity.SaveChanges(); 
            }
        }
 
 
 
UG Link: 
 
 
If you still facing the issue after trying the above way, then could you please set SourceType(Underlying Collection type) in your sample to resolve this issue like below, 
 
<syncfusion:SfDataGrid x:Name="dataGrid"  
                        AddNewRowPosition="Top"  
                        AllowEditing="True"  
                        AllowFiltering="True"  
                        AllowGrouping="True"  
                        AllowSorting="True"  
                        AutoGenerateColumns="True"  
                        SourceType="{x:Type local:Category}"  
                        ItemsSource="{Binding Orders}" />  
 
 
Regards, 
Jai Ganesh S 


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