C#截取屏幕↑

王朝c#·作者佚名  2006-01-09
窄屏简体版  字體: |||超大  

今天无聊翻代码,翻出来一个以前写的C#截屏的函数...拿出来和大家共享一下.

这段代码是参照网上一段截屏的C++代码改写的.只不过把API都声明了一下而已.

声明的各API也附后.以供参照.如有问题欢迎指出.(Appledotnet@hotmail.com)

///

/// 截取部分屏幕

///

/// 左上角

/// 右下角

/// 是否全屏幕

/// 返回值Bitmap

public static Bitmap GetPartScreen(Point P1,Point P2,bool Full)

{

IntPtr hscrdc,hmemdc;

IntPtr hbitmap,holdbitmap;

int nx,ny,nx2,ny2;

nx=ny=nx2=ny2=0;

int nwidth, nheight;

int xscrn, yscrn;

hscrdc = CreateDC("DISPLAY", null, null, 0);//创建DC句柄

hmemdc = CreateCompatibleDC(hscrdc);//创建一个内存DC

xscrn = GetDeviceCaps(hscrdc, GetDeviceCapsIndex.HORZRES);//获取屏幕宽度

yscrn = GetDeviceCaps(hscrdc, GetDeviceCapsIndex.VERTRES);//获取屏幕高度

if(Full)//如果是截取整个屏幕

{

nx = 0;

ny = 0;

nx2 = xscrn;

ny2 = yscrn;

}

else

{

nx = P1.X;

ny = P1.Y;

nx2 =P2.X;

ny2 =P2.Y;

//检查数值合法性

if(nx<0)nx = 0;

if(ny<0)ny = 0;

if(nx2>xscrn)nx2 = xscrn;

if(ny2>yscrn)ny2 = yscrn;

}

nwidth = nx2 - nx;//截取范围的宽度

nheight = ny2 - ny;//截取范围的高度

hbitmap = CreateCompatibleBitmap(hscrdc, nwidth, nheight);//从内存DC复制到hbitmap句柄

holdbitmap = SelectObject(hmemdc, hbitmap);

BitBlt(hmemdc, 0, 0, nwidth, nheight,hscrdc, nx, ny,(UInt32)0xcc0020);

hbitmap = SelectObject(hmemdc, holdbitmap);

DeleteDC(hscrdc);//删除用过的对象

DeleteDC(hmemdc);//删除用过的对象

return Bitmap.FromHbitmap(hbitmap);//用Bitmap.FromHbitmap从hbitmap返回Bitmap

}

所用到的API声明:

[DllImport("gdi32.dll")]

public static extern IntPtr CreateDC(

string lpszDriver, // driver name

string lpszDevice, // device name

string lpszOutput, // not used; should be NULL

Int64 lpInitData // optional printer data

);

[DllImport("gdi32.dll")]

public static extern IntPtr CreateCompatibleDC(

IntPtr hdc // handle to DC

);

[DllImport("gdi32.dll")]

public static extern int GetDeviceCaps(

IntPtr hdc, // handle to DC

GetDeviceCapsIndex nIndex // index of capability

);

[DllImport("gdi32.dll")]

public static extern IntPtr CreateCompatibleBitmap(

IntPtr hdc, // handle to DC

int nWidth, // width of bitmap, in pixels

int nHeight // height of bitmap, in pixels

);

[DllImport("gdi32.dll")]

public static extern IntPtr SelectObject(

IntPtr hdc, // handle to DC

IntPtr hgdiobj // handle to object

);

[DllImport("gdi32.dll")]

public static extern int BitBlt(

IntPtr hdcDest, // handle to destination DC

int nXDest, // x-coord of destination upper-left corner

int nYDest, // y-coord of destination upper-left corner

int nWidth, // width of destination rectangle

int nHeight, // height of destination rectangle

IntPtr hdcSrc, // handle to source DC

int nXSrc, // x-coordinate of source upper-left corner

int nYSrc, // y-coordinate of source upper-left corner

UInt32 dwRop // raster operation code

);

[DllImport("gdi32.dll")]

public static extern int DeleteDC(

IntPtr hdc // handle to DC

);

 
 
 
免责声明:本文为网络用户发布,其观点仅代表作者个人观点,与本站无关,本站仅提供信息存储服务。文中陈述内容未经本站证实,其真实性、完整性、及时性本站不作任何保证或承诺,请读者仅作参考,并请自行核实相关内容。
 
 
© 2005- 王朝網路 版權所有 導航