Locate a record in a C# CollectionViewSource

Question

I have a CollectionViewSource that contains a set of indexed records extracted from an MS SQL Server Table called Example using Entity framework 6.2.

Example is declared as a DbSet property of my DbContext class viz:

public virtual DbSet<Example> Examples { get; set; }

My CollectionViewSource is:

CollectionViewSource exampleViewSource;

I can move around the collection and count the number of records it contains using the following for example:

int selectedRecordPosition = exampleViewSource.View.CurrentPosition;
exampleViewSource.View.MoveCurrentToPrevious();
int numberOfRecordsInCollectionView = exampleViewSource.View.SourceCollection.Cast<Example>().Count();

How can I find a particular record in the collection and set it as the record pointer's current location?

I'm looking for something like:

    var selectedObject = exampleViewSource.View.SourceCollection.Find(key1, key2);   // example pseudo code.        
    exampleViewSource.View.MoveCurrentTo(selectedObject);

key1 & key2 are the Primary access keys for the Example tables' rows.

Can anyone help please?

What is not working with your code? Are you struggling with the filter query? How does a Example item relate to key1 and key2? — BionicCode
Hi Bionic. As said above "I have a CollectionViewSource that contains a set of indexed records extracted from an MS SQL Server Table called Example using Entity framework 6.2." and "key1 & key2 are the Primary access keys for the Example tables' rows." Together, key1 and key2 uniquely index each row of the Example table. — Joe

Joe Joe · Accepted Answer · 2020-02-03T05:37:39

BionicCode provided a solution my question but someone must have deleted it. Based on BionicCode's answer I coded ….

Example selectedObject = exampleViewSource.View.SourceCollection.Cast<Example>()
                         .Where(selectedRecord =>
                          selectedRecord.Column1Name == key1 && 
                          selectedRecord.Column2Name == key2)
                         .FirstOrDefault();
if (selectedObject == null) break;
exampleViewSource.View.MoveCurrentTo(selectedObject);

The only difference is that BionicCode didn't use a Cast and his post disappeared before I could follow it exactly. Anyway, many thanks BionicCode - you got me off the hook.

Locate a record in a C# CollectionViewSource

1 Answers