//Show the summary in the message box
        private void BtnSummary_Click(object sender, EventArgs e)
        {
            string outputString = "";

            //check data exists in the repo
            if (salesPersonRepo.Count > 0)
            {
                //if individual information is not cleared the show the appropriate result to messagebox
                if (individualSalesPersonInfoCleared)
                {
                    outputString = "Current sales person's information removed or cleared";
                }
                else
                {
                    //Check current sales person exists or not
                    if (!SalesPersonUtility.IsEmpty(aSalesPerson.FirstName) && !SalesPersonUtility.IsEmpty(aSalesPerson.LastName) &&
                        SalesPersonUtility.IsSalesPersonFound(aSalesPerson, salesPersonRepo))
                    {
                        outputString = "";

                        outputString = aSalesPerson.Display();

                        richTextBoxForResult.Text = outputString;
                    }
                    else
                    {
                        outputString = "Current sales person's information removed or cleared";
                    }
                }

                //grab and hold the value from displaySummary and also pass outputString extracted from above logic
                outputString = DisplaySummary(outputString);

                MessageBox.Show(outputString);

                richTextBoxForResult.Text = outputString;
            }

            //if no data found in the repo display appropriate message
            else
            {
                richTextBoxForResult.Text = "No data found to display";
                MessageBox.Show("No data found to display");
            }

            Clear_Error_Message();

            individualSalesPersonInfoCleared = false;
        }