private void buttonOpenClose_Click(object sender, EventArgs e) { if (buttonOpenClose.Text == "关闭") { if (comm.IsOpen) { comm.Close(); } buttonOpenClose.Text = "打开"; return; } //根据当前串口对象,来判断操作 if (comm == null) { //关闭时点击,则设置好端口,波特率后打开 comm.PortName = comboPortName.Text; comm.BaudRate = int.Parse(comboBaudrate.Text); comm.DataBits = 8; comm.Parity = Parity.None; comm.StopBits = StopBits.One; comm.WriteBufferSize = 1024 * 1024 * 5; comm.ReadBufferSize = 1024 * 1024 * 5; try { comm.Open(); MessageBox.Show("串口已打开"); } catch (Exception ex) { //捕获到异常信息,创建一个新的comm对象,之前的不能用了。 comm = new SerialPort(); //现实异常信息给客户。 MessageBox.Show(ex.Message); } } else { if (comm.IsOpen) { while (CVar.GetCommBusy()) { Application.DoEvents(); } //打开时点击,则关闭串口 comm.Close(); MessageBox.Show("串口已关闭"); } else { //关闭时点击,则设置好端口,波特率后打开 comm.PortName = comboPortName.Text; comm.BaudRate = int.Parse(comboBaudrate.Text); comm.DataBits = 8; comm.Parity = Parity.Even; comm.StopBits = StopBits.One; comm.WriteBufferSize = 1024 * 1024 * 5; comm.ReadBufferSize = 1024 * 1024 * 5; try { comm.Open(); MessageBox.Show("串口已打开"); } catch (Exception ex) { //捕获到异常信息,创建一个新的comm对象,之前的不能用了。 comm = new SerialPort(); //现实异常信息给客户。 MessageBox.Show(ex.Message); } } } //设置按钮的状态 buttonOpenClose.Text = comm.IsOpen ? "关闭" : "打开"; if (comm.IsOpen) { CommPara.portnum = comm.PortName; CommPara.baudrate = comm.BaudRate; CommPara.ParaWrite(); CVar.form1.button1.Text = CommPara.portnum.ToString() + "已打开"; comm.DataReceived += CVar.form1.comm_DataReceived; } }