private void btnHelp_Click(object sender, EventArgs e) { //replace the elements from Candidates user controler this.pnlFunctionViewr.Controls.Clear(); var HelpSupport = new HelpAndSupport(); this.pnlFunctionViewr.Controls.Add(HelpSupport); //change the background color ClearButtonBackground(); btnHelp.ForeColor = Color.White; btnHelp.BackColor = Color.Orange; }