public static void ChangeButtonTo(string btn) { if (statusForm.btnStop.InvokeRequired) { ChangeButtonCallback d = new ChangeButtonCallback(ChangeButtonTo); statusForm.Invoke(d, new object[] { btn }); } else { //statusForm.btnClose.Visible = !(statusForm.btnClose.Visible); //statusForm.btnStop.Visible = !(statusForm.btnStop.Visible); if (btn.Equals("Stop")) { statusForm.btnStop.Visible = true; statusForm.btnClose.Visible = false; } else { statusForm.btnStop.Visible = false; statusForm.btnClose.Visible = true; } } }