Question

Is there a way to prevent user to select cells in a particular dgvRow.
Row is ReadOnly, but still – selectable.

Answer 1

You can add a custom delegate that unselects the cells in question whenever the selection is changed.

DataGridView1.SelectionChanged += new EventHandler(DataGridView1_SelectionChanged);
private void DataGridView1_SelectionChanged(object sender, EventArgs e){
    List<DataGridViewCell> toBeRemoved = new List<DataGridViewCell>();
    foreach(DataGridViewCell selectedCell in DataGridView1.SelectedCells){
        if (isCellUnSelectable(selectedCell))
            toBeRemoved.Add(selectedCell);
    }
    foreach(DataGridViewCell cell in toBeRemoved){
        cell.Selected = false;
    }
}