c# backgroundWorker and trackBar

本文关键字:trackBar and backgroundWorker | 更新日期: 2023-09-27 18:11:07

部分代码:

锁定bitmapData的函数:

    public static BitmapData LockData(Bitmap bitmap)
    {
        Rectangle bitmapRect = new Rectangle(0, 0, bitmap.Width, bitmap.Height);
        BitmapData bitmapData = bitmap.LockBits(bitmapRect, ImageLockMode.ReadWrite, bitmap.PixelFormat);
        return bitmapData;
    }

解锁bitnapData的函数:

    public static void UnlockData(Bitmap bitmap, BitmapData bitmapData)
    {
        bitmap.UnlockBits(bitmapData);
    }

改变图像亮度的功能:

    public static void Bright(int bright, BitmapData bitmapData, BackgroundWorker worker, DoWorkEventArgs e)
    {
        byte nPixelFormat = 0;
        if (bitmapData.PixelFormat == PixelFormat.Format24bppRgb) nPixelFormat = 3;
        else if (bitmapData.PixelFormat == PixelFormat.Format32bppArgb) nPixelFormat = 4;
        int max = bitmapData.Height - 1;
        int percent = 0;
        unsafe
        {
            for (int y = 0; y < bitmapData.Height; y++)
            {
                byte* pBmpRow = (byte*)(bitmapData.Scan0 + y * bitmapData.Stride);
                for (int x = 0; x < bitmapData.Width; x++)
                {
                    if (worker.CancellationPending)
                    {
                        e.Cancel = true;
                        return;
                    }
                    int bVal = pBmpRow[nPixelFormat * x] + bright;
                    int gVal = pBmpRow[nPixelFormat * x + 1] + bright;
                    int rVal = pBmpRow[nPixelFormat * x + 2] + bright;

                    Clamp(ref bVal);
                    Clamp(ref gVal);
                    Clamp(ref rVal);

                    pBmpRow[nPixelFormat * x] = (byte)bVal;
                    pBmpRow[nPixelFormat * x + 1] = (byte)gVal;
                    pBmpRow[nPixelFormat * x + 2] = (byte)rVal;
                }
                //System.Threading.Thread.Sleep(5);
                int curPercent = (y * 100) / max;
                if (curPercent > percent)
                {
                    percent = curPercent;
                    worker.ReportProgress(percent);
                }
            }
        }
    }

在这个函数中,我正在检查backgroundWorker abort并更新进度。

现在我有w trackbar和numericBox,我用它来改变亮度。当trackbar或numericBox的值改变时,backgroundWorker启动。问题是,当backgroundWorker很忙,我已经改变了trackbarValue, backgroundWorker应该停止并重新启动。现在在我的代码中,它像按钮一样工作。当工作线程忙时,修改值将停止工作线程,然后下一次修改值将启动它。

代码:

    private void OnNumericBoxValueChanged(object sender, EventArgs e)
    {

        m_trkBarBright.Value = (int)m_numericBright.Value;
        brightValue = m_trkBarBright.Value;
        if (backgroundWorker.IsBusy)
        {
            backgroundWorker.CancelAsync();
        }
        else
        {
            backgroundWorker.RunWorkerAsync();
        }

        m_btnOK.Focus();
    }

    private void WorkerDoWork(object sender, DoWorkEventArgs e)
    {
        BackgroundWorker worker = (BackgroundWorker)sender;

        Colors.CopyImgData(m_orgImage, m_tempImage);
        data = Colors.LockData(m_tempImage);
        Colors.Bright(brightValue, data,worker, e);
    }
    private void WorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
    {
        if (e.Error != null)
        {
            Colors.UnlockData(m_tempImage, data);
            MessageBox.Show(e.Error.Message);
            progressBar1.Value = 0;
        }
        else if (e.Cancelled)
        {
            Colors.UnlockData(m_tempImage, data);
            if(!exit)
            m_imgBox.UpdateImage(m_tempImage);
            MessageBox.Show("Canceled");
            progressBar1.Value = 0;
        }
        else
        {
            Colors.UnlockData(m_tempImage, data);
            if (!exit)
            m_imgBox.UpdateImage(m_tempImage);
            progressBar1.Value = 0;
            MessageBox.Show("Done");
        }
    }
    private void WorkerProgress(object sender, ProgressChangedEventArgs e)
    {
        progressBar1.Value = e.ProgressPercentage;
    }

有人知道如何解决这个问题吗?

c# backgroundWorker and trackBar

正确的方法是检查backgroundWorker.CancellationPending并从WorkerDoWork设置e.Cancel = true

CancelAsync不停止worker,它只是向线程发送消息说"我想停止"。