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?
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"。