panel上可以通过DrawToBitmap截图，不管是否在屏幕外是否有遮挡
Bitmap sourceBitmap = new Bitmap(400, 300);
//Control ct = frmMain.mianForm.panel1 as Control;
//ct.DrawToBitmap(sourceBitmap, new System.Drawing.Rectangle(0, 0, 400, 300));
panel1.DrawToBitmap(sourceBitmap, new System.Drawing.Rectangle(0, 0, 400, 300));
sourceBitmap.Save(@"e:\123form2.bmp");
在图片上打水印
string strpath = @"e:\1.bmp";
Bitmap bmp = new Bitmap(strpath);
Graphics graphics = Graphics.FromImage(bmp);
System.Drawing.SolidBrush myBrush = new System.Drawing.SolidBrush(System.Drawing.Color.Red);
graphics.FillEllipse(myBrush, new System.Drawing.Rectangle(150, 200, 10, 10));//画圆
try
{
bmp.Save(@"e:\new.bmp");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
抓屏截图
Image objImage = new Bitmap(400, 300);
Graphics g = Graphics.FromImage(objImage);
g.CopyFromScreen(new System.Drawing.Point(Cursor.Position.X - 150, Cursor.Position.Y - 25), new System.Drawing.Point(0, 0), new Size(400, 300));
IntPtr dc1 = g.GetHdc();
g.ReleaseHdc(dc1);
objImage.Save("e:\\test.jpg");
非顶端窗口截图
用Windows热键截图然后保存的我就不说了,地球人都知道.
如何截取非前端窗体的截图，要先获取所要截图的窗口的句柄IntPtr PicWindow = this.Handle
首先说一下PrintWindow这个API的使用
public static Bitmap GetWindowCapture(IntPtr hWnd)
{
IntPtr hscrdc = GetWindowDC(hWnd);
RECT windowRect = new RECT();
GetWindowRect(hWnd, ref windowRect);
int width = windowRect.right - windowRect.left;
int height = windowRect.bottom - windowRect.top;
IntPtr hbitmap = CreateCompatibleBitmap(hscrdc, width, height);
IntPtr hmemdc = CreateCompatibleDC(hscrdc);
SelectObject(hmemdc, hbitmap);
PrintWindow(hWnd, hmemdc, 0);
Bitmap bmp = Bitmap.FromHbitmap(hbitmap);
DeleteDC(hscrdc);//删除用过的对象
DeleteDC(hmemdc);//删除用过的对象
return bmp;
}
[DllImport("user32.dll")]
public static extern IntPtr GetWindowRect(IntPtr hWnd, ref RECT rect);
[DllImport("gdi32.dll")]
public static extern IntPtr CreateDC(
string lpszDriver, // driver name驱动名
string lpszDevice, // device name设备名
string lpszOutput, // not used; should be NULL
IntPtr lpInitData // optional printer data
);
[DllImport("gdi32.dll")]
public static extern int BitBlt(
IntPtr hdcDest, // handle to destination DC目标设备的句柄
int nXDest, // x-coord of destination upper-left corner目标对象的左上角的X坐标
int nYDest, // y-coord of destination upper-left corner目标对象的左上角的Y坐标
int nWidth, // width of destination rectangle目标对象的矩形宽度
int nHeight, // height of destination rectangle目标对象的矩形长度
IntPtr hdcSrc, // handle to source DC源设备的句柄
int nXSrc, // x-coordinate of source upper-left corner源对象的左上角的X坐标
int nYSrc, // y-coordinate of source upper-left corner源对象的左上角的Y坐标
UInt32 dwRop // raster operation code光栅的操作值
);
[DllImport("gdi32.dll")]
public static extern IntPtr CreateCompatibleDC(
IntPtr hdc // handle to DC
);
[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 DeleteDC(
IntPtr hdc // handle to DC
);
[DllImport("user32.dll")]
public static extern bool PrintWindow(
IntPtr hwnd, // Window to copy,Handle to the window that will be copied.
IntPtr hdcBlt, // HDC to print into,Handle to the device context.
UInt32 nFlags // Optional flags,Specifies the drawing options. It can be one of the following values.
);
[DllImport("user32.dll")]
public static extern IntPtr GetWindowDC(
IntPtr hwnd
);
很遗憾,上面的确可以截取非前端窗体的截图,但是非GDI的程序是无法截图的比如DirectX
下面说一下BitBlt这个API的使用
/// <summary>
/// 提供全屏和指定窗口的截图 以及保存为文件的类
/// </summary>
public class ScreenCapture
{
/// <summary>
/// 全屏截图
/// </summary>
/// <returns></returns>
public Image CaptureScreen()
{
return CaptureWindow(User32.GetDesktopWindow());
}
/// <summary>
/// 指定窗口截图
/// </summary>
/// <param name="handle">窗口句柄. (在windows应用程序中, 从Handle属性获得)</param>
/// <returns></returns>
public Image CaptureWindow(IntPtr handle)
{
IntPtr hdcSrc = User32.GetWindowDC(handle);
User32.RECT windowRect = new User32.RECT();
User32.GetWindowRect(handle, ref windowRect);
int width = windowRect.right - windowRect.left;
int height = windowRect.bottom - windowRect.top;
IntPtr hdcDest = GDI32.CreateCompatibleDC(hdcSrc);
IntPtr hBitmap = GDI32.CreateCompatibleBitmap(hdcSrc, width, height);
IntPtr hOld = GDI32.SelectObject(hdcDest, hBitmap);
GDI32.BitBlt(hdcDest, 0, 0, width, height, hdcSrc, 0, 0, GDI32.SRCCOPY);
GDI32.SelectObject(hdcDest, hOld);
GDI32.DeleteDC(hdcDest);