/// <summary>
/// when the selection of a spreadsheet is changed, updates values of name, contents, and value of spreadsheet.
///
/// </summary>
/// <param name="sender"></param>
private void OnSelectionChanged(SpreadsheetPanel sender)
{
// Get where we are in the spreadsheet
sender.GetSelection(out int col, out int row);
// Update name textBox
textBoxCellName.Text = (ConvertCellName(col, row));
// Update value textBox
sender.GetValue(col, row, out string val);
textBoxCellValue.Text = val;
// Update contents textBox
textBoxCellContents.Text = sender.GetContents(col, row);
// Focus the input onto the contents textbox
textBoxCellContents.Focus();
// Sending selection changed to server via JSon
RequestTypeSelection r = new RequestTypeSelection("selectCell", spreadsheetPanel1.ConvertCellName(col, row));
string request = JsonConvert.SerializeObject(r) + "\n";
NC.SendData(request);
}