Question

I get the following error when adding an entity
“An entity with the same identity already exists in this EntitySet”
The frustrating part is that it is an intermittent issue and it is very hard for me to reproduce.
My code:

     private void OKButton_Click(object sender, RoutedEventArgs e)
    {
        this.IsHitTestVisible = false;
        Form Form = _context.Forms.FirstOrDefault();

        Form.Transactions.Add(new Transactions
        {
            Comments = textbox_taskcomments.Text,
            By = UserID,
            Name = Name,
            IssuedOn = DateTime.Now,
            StatusID = StatusID
        });

        this.DialogResult = DevExpress.Xpf.Core.DialogResult.OK;
        this.Close();
    }

Any help would be appreciated as I do not know where to start….

Thanks

Answer 1

Have you tried the contains method?

Contains: Specifies whether the EntitySet contains a specific entity.

You should be checking the contents of the EntitySet before you modify it.

 Transactions t = new Transactions{
        Comments = textbox_taskcomments.Text,
        By = UserID,
        Name = Name,
        IssuedOn = DateTime.Now,
        StatusID = StatusID
 };
 //check that the entity does not yet contain t
 if(!Form.Transactions.Contains(t)){
 //do something.
 }

(I don’t know the rest of your code but.. from what I’ve read, this might be a solution)