DataGridView throwing “InvalidOperationException: Operation is not valid…” when adding a row

Question

I want an OpenFileDialog to come up when a user clicks on a cell, then display the result in the cell.

It all works, except that the DataGridView displays an extra row,

Answer 1

I found a workaround on this page, though I don't know why it works

public MyForm()
{
    InitializeComponent();
    //Create a BindingSource, set its DataSource to my list,
    //set the DataGrid's DataSource to the BindindingSource...
    _bindingSource.AddingNew += OnAddingNewToBindingSource;
}

private void OnAddingNewToBindingSource(object sender, AddingNewEventArgs e)
{
    if(dataGridView1.Rows.Count == _bindingSource.Count)
    {
        _bindingSource.RemoveAt(_bindingSource.Count - 1);
    }
}

I'm getting very sick of spending so much time dealing with Visual Studio bugs...