由于内存释放问题,使用BitBlt方法会导致内存占用慢慢长大而不会被释放,使用普通的双缓冲没有这个问题,而且速度可以
由于是裁剪了部分代码,因此存在代码不完整的问题
Cementing.CurveSplit.DrawCurvePress 再memDC指向的位图(memBmp)上画压力曲线图,其它类似private Graphics memDC; //屏幕外的图像
private Graphics clientDC;
private Bitmap memBmp;
private static SolidBrush backBrush;
#region DrawCurve BitBltprivate void DrawCurveBitBlt(int p_ScrollValue)
{
try
{
if (m_RealTime == true)
{
mAL = Cementing.PortValues.AL; //曲线图数据来源,mAL是System.Collections.ArrayList mAL
} if (memBmp == null) //初始化要双缓冲的位图
{
memBmp = null;
memBmp = new Bitmap(m_intWidth, m_intHeight);
}
else
{
if ((mWidthOld != m_intWidth) || (mHeightOld != m_intHeight)) //位图尺寸发生了变化
{
memBmp = null;
mWidthOld = m_intWidth;
mHeightOld = m_intHeight;
memBmp = new Bitmap(m_intWidth, m_intHeight);
}
} clientDC = this.CreateGraphics(); //获取绘图区的Graphics IntPtr hdc = clientDC.GetHdc();
IntPtr memdc = Win32Support.CreateCompatibleDC(hdc);
Win32Support.SelectObject(memdc, memBmp.GetHbitmap());
memDC = Graphics.FromHdc(memdc);
double pWidth = (double)(m_intWidth - m_H) / (double)m_WidthRange;
double pHeight = (double)(m_intHeight - m_V) / (double)m_HeightRange; memDC.FillRectangle(Brushes.White, 0, 0, m_intWidth, m_intHeight); switch (m_intType)
{
case 1:
SetScrollBar();
Cementing.CurveSplit.DrawCurvePress(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
case 2:
SetScrollBar();
Cementing.CurveSplit.DrawCurvePressDif(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
case 3:
SetScrollBar();
Cementing.CurveSplit.DrawCurveRate(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
case 4:
SetScrollBar();
Cementing.CurveSplit.DrawCurveTemperature(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
} IntPtr hMemdc = memDC.GetHdc();
Win32Support.BitBlt(hdc, 0, 0, m_intWidth, m_intHeight, hMemdc, 0, 0, Win32Support.TernaryRasterOperations.SRCCOPY); clientDC.ReleaseHdc(hdc);
memDC.ReleaseHdc(hMemdc); }
catch (NullReferenceException NullEx)
{
throw NullEx;
}
catch (Exception ex)
{
throw ex;
}}#endregion DrawCurve BitBlt#region DrawCurveprivate void DrawCurve(int p_ScrollValue)
{
try
{
if (m_RealTime == true)
{
mAL = Cementing.PortValues.AL; //曲线图数据来源,mAL是System.Collections.ArrayList mAL
} if (memBmp == null) //初始化要双缓冲的位图
{
memBmp = null;
memBmp = new Bitmap(m_intWidth, m_intHeight);
}
else
{
if ((mWidthOld != m_intWidth) || (mHeightOld != m_intHeight))
{
memBmp = null;
mWidthOld = m_intWidth;
mHeightOld = m_intHeight;
memBmp = new Bitmap(m_intWidth, m_intHeight);
}
} memDC = Graphics.FromImage(memBmp);
memDC.Clear(Color.White);
backBrush = new SolidBrush(Color.White);
memDC.FillRectangle(backBrush, 0, 0, m_intWidth, m_intHeight); switch (m_intType)
{
case 1:
SetScrollBar();
Cementing.CurveSplit.DrawCurvePress(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
case 2:
SetScrollBar();
Cementing.CurveSplit.DrawCurvePressDif(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
case 3:
SetScrollBar();
Cementing.CurveSplit.DrawCurveRate(memDC, p_ScrollValue, mAL, mPen, backBrush, m_RealTime, m_intWidth, m_intHeight);
break;
case 4:
SetScrollBar();
Cementing.CurveSplit.DrawCurveTemperature(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
} clientDC = this.CreateGraphics();
clientDC.DrawImage(memBmp, 0, 0);
}
catch (NullReferenceException NullEx)
{
throw NullEx;
}
catch (Exception ex)
{
throw ex;
}}#endregion DrawCurve
由于是裁剪了部分代码,因此存在代码不完整的问题
Cementing.CurveSplit.DrawCurvePress 再memDC指向的位图(memBmp)上画压力曲线图,其它类似private Graphics memDC; //屏幕外的图像
private Graphics clientDC;
private Bitmap memBmp;
private static SolidBrush backBrush;
#region DrawCurve BitBltprivate void DrawCurveBitBlt(int p_ScrollValue)
{
try
{
if (m_RealTime == true)
{
mAL = Cementing.PortValues.AL; //曲线图数据来源,mAL是System.Collections.ArrayList mAL
} if (memBmp == null) //初始化要双缓冲的位图
{
memBmp = null;
memBmp = new Bitmap(m_intWidth, m_intHeight);
}
else
{
if ((mWidthOld != m_intWidth) || (mHeightOld != m_intHeight)) //位图尺寸发生了变化
{
memBmp = null;
mWidthOld = m_intWidth;
mHeightOld = m_intHeight;
memBmp = new Bitmap(m_intWidth, m_intHeight);
}
} clientDC = this.CreateGraphics(); //获取绘图区的Graphics IntPtr hdc = clientDC.GetHdc();
IntPtr memdc = Win32Support.CreateCompatibleDC(hdc);
Win32Support.SelectObject(memdc, memBmp.GetHbitmap());
memDC = Graphics.FromHdc(memdc);
double pWidth = (double)(m_intWidth - m_H) / (double)m_WidthRange;
double pHeight = (double)(m_intHeight - m_V) / (double)m_HeightRange; memDC.FillRectangle(Brushes.White, 0, 0, m_intWidth, m_intHeight); switch (m_intType)
{
case 1:
SetScrollBar();
Cementing.CurveSplit.DrawCurvePress(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
case 2:
SetScrollBar();
Cementing.CurveSplit.DrawCurvePressDif(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
case 3:
SetScrollBar();
Cementing.CurveSplit.DrawCurveRate(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
case 4:
SetScrollBar();
Cementing.CurveSplit.DrawCurveTemperature(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
} IntPtr hMemdc = memDC.GetHdc();
Win32Support.BitBlt(hdc, 0, 0, m_intWidth, m_intHeight, hMemdc, 0, 0, Win32Support.TernaryRasterOperations.SRCCOPY); clientDC.ReleaseHdc(hdc);
memDC.ReleaseHdc(hMemdc); }
catch (NullReferenceException NullEx)
{
throw NullEx;
}
catch (Exception ex)
{
throw ex;
}}#endregion DrawCurve BitBlt#region DrawCurveprivate void DrawCurve(int p_ScrollValue)
{
try
{
if (m_RealTime == true)
{
mAL = Cementing.PortValues.AL; //曲线图数据来源,mAL是System.Collections.ArrayList mAL
} if (memBmp == null) //初始化要双缓冲的位图
{
memBmp = null;
memBmp = new Bitmap(m_intWidth, m_intHeight);
}
else
{
if ((mWidthOld != m_intWidth) || (mHeightOld != m_intHeight))
{
memBmp = null;
mWidthOld = m_intWidth;
mHeightOld = m_intHeight;
memBmp = new Bitmap(m_intWidth, m_intHeight);
}
} memDC = Graphics.FromImage(memBmp);
memDC.Clear(Color.White);
backBrush = new SolidBrush(Color.White);
memDC.FillRectangle(backBrush, 0, 0, m_intWidth, m_intHeight); switch (m_intType)
{
case 1:
SetScrollBar();
Cementing.CurveSplit.DrawCurvePress(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
case 2:
SetScrollBar();
Cementing.CurveSplit.DrawCurvePressDif(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
case 3:
SetScrollBar();
Cementing.CurveSplit.DrawCurveRate(memDC, p_ScrollValue, mAL, mPen, backBrush, m_RealTime, m_intWidth, m_intHeight);
break;
case 4:
SetScrollBar();
Cementing.CurveSplit.DrawCurveTemperature(memDC, p_ScrollValue, mAL, mPen, backBrush, m_intWidth, m_intHeight);
break;
} clientDC = this.CreateGraphics();
clientDC.DrawImage(memBmp, 0, 0);
}
catch (NullReferenceException NullEx)
{
throw NullEx;
}
catch (Exception ex)
{
throw ex;
}}#endregion DrawCurve
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;namespace Cementing
{
class Win32Support
{
/// <summary>
/// Enumeration to be used for those Win32 function that return BOOL
/// </summary>
public enum Bool
{
False = 0,
True
}; /// <summary>
/// Enumeration for the raster operations used in BitBlt.
/// In C++ these are actually #define. But to use these
/// constants with C#, a new enumeration type is defined.
/// </summary>
public enum TernaryRasterOperations
{
SRCCOPY = 0x00CC0020, /* dest = source */
SRCPAINT = 0x00EE0086, /* dest = source OR dest */
SRCAND = 0x008800C6, /* dest = source AND dest */
SRCINVERT = 0x00660046, /* dest = source XOR dest */
SRCERASE = 0x00440328, /* dest = source AND (NOT dest ) */
NOTSRCCOPY = 0x00330008, /* dest = (NOT source) */
NOTSRCERASE = 0x001100A6, /* dest = (NOT src) AND (NOT dest) */
MERGECOPY = 0x00C000CA, /* dest = (source AND pattern) */
MERGEPAINT = 0x00BB0226, /* dest = (NOT source) OR dest */
PATCOPY = 0x00F00021, /* dest = pattern */
PATPAINT = 0x00FB0A09, /* dest = DPSnoo */
PATINVERT = 0x005A0049, /* dest = pattern XOR dest */
DSTINVERT = 0x00550009, /* dest = (NOT dest) */
BLACKNESS = 0x00000042, /* dest = BLACK */
WHITENESS = 0x00FF0062, /* dest = WHITE */
}; /// <summary>
/// CreateCompatibleDC
/// </summary>
[DllImport("gdi32.dll", ExactSpelling = true, SetLastError = true)]
public static extern IntPtr CreateCompatibleDC(IntPtr hDC); /// <summary>
/// DeleteDC
/// </summary>
[DllImport("gdi32.dll", ExactSpelling = true, SetLastError = true)]
public static extern Bool DeleteDC(IntPtr hdc); /// <summary>
/// SelectObject
/// </summary>
[DllImport("gdi32.dll", ExactSpelling = true)]
public static extern IntPtr SelectObject(IntPtr hDC, IntPtr hObject); /// <summary>
/// DeleteObject
/// </summary>
[DllImport("gdi32.dll", ExactSpelling = true, SetLastError = true)]
public static extern Bool DeleteObject(IntPtr hObject); /// <summary>
/// CreateCompatibleBitmap
/// </summary>
[DllImport("gdi32.dll", ExactSpelling = true, SetLastError = true)]
public static extern IntPtr CreateCompatibleBitmap(IntPtr hObject, int width, int height); /// <summary>
/// BitBlt
/// </summary>
[DllImport("gdi32.dll", ExactSpelling = true, SetLastError = true)]
public static extern Bool BitBlt(IntPtr hObject, int nXDest, int nYDest, int nWidth, int nHeight, IntPtr hObjSource, int nXSrc, int nYSrc, TernaryRasterOperations dwRop);
}
}
参见VS2005的MSDN:使用双缓冲 或双缓冲图形部分,
或
如何:手动管理缓冲图形
参见VS2005的MSDN:使用双缓冲 或双缓冲图形部分,
或
如何:手动管理缓冲图形
测试了,这个方法没有我的方法顺滑,不过如果当时我就发现可以调用这个的话,就不会去写双缓冲了