private void but_open_Click(object sender, EventArgs e) { try { client?.Close(); if (chb_rtudata.Checked) { client = new ModBusTcpRtuClient(txt_ip.Text?.Trim(), int.Parse(txt_port.Text?.Trim())); } else { client = new ModBusTcpClient(txt_ip.Text?.Trim(), int.Parse(txt_port.Text?.Trim())); } var result = client.Open(); if (result.IsSucceed) { but_read.Enabled = true; but_write.Enabled = true; but_open.Enabled = false; but_close.Enabled = true; but_sendData.Enabled = true; AppendText($"连接成功"); } else { MessageBox.Show($"连接失败:{result.Err}"); } } catch (Exception ex) { MessageBox.Show(ex.Message); } }