C# 如何在C语言中截取全尺寸窗口的屏幕截图#
我正在尝试在C#.net中创建一个应用程序,用于捕获当前活动窗口的屏幕截图,包括必须使用滚动条滚动的区域。要非常清楚,我希望代码采取的活动窗口,包括该地区是不显示,只有通过使用滚动条显示屏幕截图C# 如何在C语言中截取全尺寸窗口的屏幕截图#,c#,screenshot,fullscreen,winapi,C#,Screenshot,Fullscreen,Winapi,我正在尝试在C#.net中创建一个应用程序,用于捕获当前活动窗口的屏幕截图,包括必须使用滚动条滚动的区域。要非常清楚,我希望代码采取的活动窗口,包括该地区是不显示,只有通过使用滚动条显示屏幕截图 public class ScreenShot { /// <summary> /// Captures the screenshot of the entire desktop /// </summary> /// <returns>
public class ScreenShot
{
/// <summary>
/// Captures the screenshot of the entire desktop
/// </summary>
/// <returns>Image object containing the screenshot of the desktop</returns>
private Image CaptureDesktop()
{
return CaptureWindow(User32.GetDesktopWindow());
}
public Image CaptureAciveWindow()
{
return CaptureWindow(User32.GetForegroundWindow());
}
/// <summary>
/// An Internal method, that captures the screenshot of any given Application window, given its Handle.
/// </summary>
/// <param name="handle">The handle of the window you want to Capture</param>
/// <returns>An Image object containing the screenshot of the active application window</returns>
private Image CaptureWindow(IntPtr handle)
{
// get te hDC of the target window
IntPtr hdcSrc = User32.GetWindowDC(handle);
// get the size
User32.RECT windowRect = new User32.RECT();
User32.GetWindowRect(handle, ref windowRect);
int width = windowRect.right - windowRect.left;
int height = windowRect.bottom - windowRect.top;
// create a device context we can copy to
IntPtr hdcDest = GDI32.CreateCompatibleDC(hdcSrc);
// create a bitmap we can copy it to,
// using GetDeviceCaps to get the width/height
IntPtr hBitmap = GDI32.CreateCompatibleBitmap(hdcSrc, width, height);
// select the bitmap object
IntPtr hOld = GDI32.SelectObject(hdcDest, hBitmap);
// bitblt over
GDI32.BitBlt(hdcDest, 0, 0, width, height, hdcSrc, 0, 0, GDI32.SRCCOPY);
// restore selection
GDI32.SelectObject(hdcDest, hOld);
// clean up
GDI32.DeleteDC(hdcDest);
User32.ReleaseDC(handle, hdcSrc);
// get a .NET image object for it
Image img = Image.FromHbitmap(hBitmap);
// free up the Bitmap object
GDI32.DeleteObject(hBitmap);
return img;
}
/// <summary>
/// Helper class containing Gdi32 API functions
/// </summary>
private class GDI32
{
public const int SRCCOPY = 0x00CC0020; // BitBlt dwRop parameter
[DllImport("gdi32.dll")]
public static extern bool BitBlt(IntPtr hObject, int nXDest, int nYDest,
int nWidth, int nHeight, IntPtr hObjectSource,
int nXSrc, int nYSrc, int dwRop);
[DllImport("gdi32.dll")]
public static extern IntPtr CreateCompatibleBitmap(IntPtr hDC, int nWidth,
int nHeight);
[DllImport("gdi32.dll")]
public static extern IntPtr CreateCompatibleDC(IntPtr hDC);
[DllImport("gdi32.dll")]
public static extern bool DeleteDC(IntPtr hDC);
[DllImport("gdi32.dll")]
public static extern bool DeleteObject(IntPtr hObject);
[DllImport("gdi32.dll")]
public static extern IntPtr SelectObject(IntPtr hDC, IntPtr hObject);
}
/// <summary>
/// Helper class containing User32 API functions
/// </summary>
private class User32
{
[StructLayout(LayoutKind.Sequential)]
public struct RECT
{
public int left;
public int top;
public int right;
public int bottom;
}
[DllImport("user32.dll")]
public static extern IntPtr GetDesktopWindow();
[DllImport("user32.dll")]
public static extern IntPtr GetWindowDC(IntPtr hWnd);
[DllImport("user32.dll")]
public static extern IntPtr ReleaseDC(IntPtr hWnd, IntPtr hDC);
[DllImport("user32.dll")]
public static extern IntPtr GetWindowRect(IntPtr hWnd, ref RECT rect);
/// <summary>
/// Gets the Handle for current active window
/// </summary>
/// <returns>Active windows Handle</returns>
[DllImport("user32.dll")]
public static extern IntPtr GetForegroundWindow();
}
}
公共类截图
{
///
///捕获整个桌面的屏幕截图
///
///包含桌面截图的图像对象
私有图像捕获桌面()
{
返回CaptureWindow(User32.GetDesktopWindow());
}
公共图像捕获活动窗口()
{
返回CaptureWindow(User32.GetForegroundWindow());
}
///
///一个内部方法,它捕获任何给定应用程序窗口的屏幕截图,给定其句柄。
///
///要捕获的窗口的句柄
///包含活动应用程序窗口屏幕截图的图像对象
私有图像捕获窗口(IntPtr句柄)
{
//获取目标窗口的te hDC
IntPtr hdcSrc=User32.GetWindowDC(句柄);
//知道尺寸了吗
User32.RECT windowRect=新的User32.RECT();
User32.GetWindowRect(句柄,ref windowRect);
int width=windowRect.right-windowRect.left;
int height=windowRect.bottom-windowRect.top;
//创建可以复制到的设备上下文
IntPtr hdcDest=GDI32.CreateCompatibleDC(hdcSrc);
//创建一个我们可以复制到的位图,
//使用GetDeviceCaps获取宽度/高度
IntPtr hBitmap=GDI32.CreateCompatibleBitmap(hdcSrc,宽度,高度);
//选择位图对象
IntPtr hOld=GDI32。选择对象(hdcDest、hBitmap);
//结束
BitBlt(hdcDest,0,0,宽度,高度,hdcSrc,0,0,GDI32.SRCCOPY);
//恢复选择
GDI32.选择对象(hdcDest,保持);
//清理
GDI32.DeleteDC(hdcDest);
User32.ReleaseDC(句柄,hdcSrc);
//为它获取一个.NET图像对象
图像img=图像。来自hBitmap(hBitmap);
//释放位图对象
GDI32.DeleteObject(hBitmap);
返回img;
}
///
///包含Gdi32 API函数的帮助器类
///
私有类GDI32
{
public const int SRCCOPY=0x00CC0020;//BitBlt dwRop参数
[DllImport(“gdi32.dll”)]
公共静态外部bool BitBlt(IntPtr hObject、intnxtest、intnydest、,
int nWidth、int nHeight、IntPtr hObjectSource、,
int nXSrc、int nYSrc、int dwRop);
[DllImport(“gdi32.dll”)]
公共静态外部IntPtr CreateCompatibleBitmap(IntPtr hDC,int nWidth,
内特(右);
[DllImport(“gdi32.dll”)]
公共静态外部IntPtr CreateCompatibleDC(IntPtr hDC);
[DllImport(“gdi32.dll”)]
公共静态外部布尔删除DC(IntPtr hDC);
[DllImport(“gdi32.dll”)]
公共静态外部bool DeleteObject(IntPtr-hObject);
[DllImport(“gdi32.dll”)]
公共静态外部IntPtr SelectObject(IntPtr hDC、IntPtr hObject);
}
///
///包含user32api函数的Helper类
///
私有类User32
{
[StructLayout(LayoutKind.Sequential)]
公共结构矩形
{
公共int左;
公共int top;
公共权利;
公共int底部;
}
[DllImport(“user32.dll”)]
公共静态外部IntPtr GetDesktopWindow();
[DllImport(“user32.dll”)]
公共静态外部IntPtr GetWindowDC(IntPtr hWnd);
[DllImport(“user32.dll”)]
公共静态外部IntPtr ReleaseDC(IntPtr hWnd、IntPtr hDC);
[DllImport(“user32.dll”)]
公共静态外部IntPtr GetWindowRect(IntPtr hWnd,ref RECT RECT);
///
///获取当前活动窗口的句柄
///
///活动窗口句柄
[DllImport(“user32.dll”)]
公共静态外部IntPtr GetForegroundWindow();
}
}
您在这里做出的假设不一定是正确的:在未卷取的区域已经有东西在等待。应用程序可以构建特定高度或宽度的滚动条,并且在用户实际拖动滚动条之前,不会向曲面实际渲染任何内容。您要捕获的图像仅存在于“潜在”中。这可以用来提高性能—考虑及时加载,或减少内存使用。这是一种相当普遍的技术,因此你所要求的并没有真正意义。如果你试图获取屏幕外的内容,那么WM\u PRINT
可能会起作用BitBlt
肯定不会
见:
或者,如果使用或切换到WPF,您可以使用PrintDialog.PrintVisual()打印控件(包括主窗口)。WM\u print也不起作用,我想没有可能的解决方案。确定可能是我必须同意您的意见