RunWorkerAsync返回忙状态

Question

我正在使用BackgroundWorker来获取数据并更新我的UI。这段代码非常自我解释。当我点击连接时，它连接到CANbus，启动后台工作程序，它获取数据并更新UI，当我点击断开连接时，它停止从CANbus获取数据。

它仅适用于第一次，当我第二次尝试连接时，我在RunWorkerAsync调用中获得异常，这是在RunWorkerCompleted回调中，关于BackgroundWorker正忙，并且它不能同时处理多个任务。

这就是我不太明白的，我在每个连接上都创建了BackgroundWorker的新实例，并且不知道为什么它很忙。

寻求建议 - 谢谢。

    CANALHandle h;
    BackgroundWorker canWorker;

    private void bConnect_Click(object sender, RoutedEventArgs e)
    {
        if (this.h == 0) {
            this.h = CANAL.CANALOpen("ED000200; 500", CANAL.FLAG_NONE);

            canWorker = new BackgroundWorker();
            canWorker.WorkerSupportsCancellation = true;
            canWorker.WorkerReportsProgress = true;
            canWorker.DoWork += (object s, DoWorkEventArgs ev) => {
                if (CANAL.CANALDataAvailable(this.h) > 0) {
                    CANALMSG msg;
                    CANALStatus st = CANAL.CANALReceive(this.h, out msg);
                    ev.Result = msg;
                }
            };
            canWorker.RunWorkerCompleted += (object s, RunWorkerCompletedEventArgs ev) => {
                if (ev.Error != null) {

                } else if (ev.Result != null) {
                    CANALMSG msg = (CANALMSG)ev.Result;

                    if (msg.id > 0) {
                        textCanId.Text = msg.id.ToString("X");
                        textCanLength.Text = msg.count.ToString("X");
                        textCanByte0.Text = (msg.count >= 1) ? msg.data[0].ToString("X2") : "";
                        textCanByte1.Text = (msg.count >= 2) ? msg.data[1].ToString("X2") : "";
                        textCanByte2.Text = (msg.count >= 3) ? msg.data[2].ToString("X2") : "";
                        textCanByte3.Text = (msg.count >= 4) ? msg.data[3].ToString("X2") : "";
                        textCanByte4.Text = (msg.count >= 5) ? msg.data[4].ToString("X2") : "";
                        textCanByte5.Text = (msg.count >= 6) ? msg.data[5].ToString("X2") : "";
                        textCanByte6.Text = (msg.count >= 7) ? msg.data[6].ToString("X2") : "";
                        textCanByte7.Text = (msg.count >= 8) ? msg.data[7].ToString("X2") : "";
                    }
                }
                canWorker.RunWorkerAsync();
            };

            canWorker.RunWorkerAsync();
        }
    }

    private void bDisconnect_Click(object sender, RoutedEventArgs e)
    {
        if (this.h > 0) {
            canWorker.CancelAsync();
            canWorker.Dispose();
            CANAL.CANALClose(this.h);
            this.h = 0;
        }
    }