使用C＃和Winforms捕获不同方式的屏幕截图

本文概述

活动的Winform窗口截图
全屏截图
更多信息

为了报告错误, 一个应用程序仅打算获取窗口的屏幕截图等。无论使用什么, 图像都可以说1000多个单词。
在本文中, 你将学习如何对监视器或仅对指定的winform窗口进行屏幕截图。
我们提供2种不同的方法来实现每种屏幕截图类型。如果要使用那些使用ScreenCapture类的方法, 则在项目中需要以下类, 代码如下, 请不要忘记根据更改命名空间你的项目之一：
注意：如果使用不需要ScreenCapture的方法, 则不需要此类, 因为可以使用仅使用CopyFromScreen方法的第二个选项。

using System; using System.Runtime.InteropServices; using System.Drawing; using System.Drawing.Imaging; namespace ChangeThisNamespace{/// < summary> /// Provides functions to capture the entire screen, or a particular window, and save it to a file./// < /summary> public class ScreenCapture{/// < summary> /// Creates an Image object containing a screen shot of the entire desktop/// < /summary> /// < returns> < /returns> public Image CaptureScreen(){return CaptureWindow(User32.GetDesktopWindow()); }/// < summary> /// Creates an Image object containing a screen shot of a specific window/// < /summary> /// < param name="handle"> The handle to the window. (In windows forms, this is obtained by the Handle property)< /param> /// < returns> < /returns> public Image CaptureWindow(IntPtr handle){// get te hDC of the target windowIntPtr hdcSrc = http://www.srcmini.com/User32.GetWindowDC(handle); // get the sizeUser32.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 toIntPtr hdcDest = GDI32.CreateCompatibleDC(hdcSrc); // create a bitmap we can copy it to, // using GetDeviceCaps to get the width/heightIntPtr hBitmap = GDI32.CreateCompatibleBitmap(hdcSrc, width, height); // select the bitmap objectIntPtr hOld = GDI32.SelectObject(hdcDest, hBitmap); // bitblt overGDI32.BitBlt(hdcDest, 0, 0, width, height, hdcSrc, 0, 0, GDI32.SRCCOPY); // restore selectionGDI32.SelectObject(hdcDest, hOld); // clean up GDI32.DeleteDC(hdcDest); User32.ReleaseDC(handle, hdcSrc); // get a .NET image object for itImage img = Image.FromHbitmap(hBitmap); // free up the Bitmap objectGDI32.DeleteObject(hBitmap); return img; }/// < summary> /// Captures a screen shot of a specific window, and saves it to a file/// < /summary> /// < param name="handle"> < /param> /// < param name="filename"> < /param> /// < param name="format"> < /param> public void CaptureWindowToFile(IntPtr handle, string filename, ImageFormat format){Image img = CaptureWindow(handle); img.Save(filename, format); }/// < summary> /// Captures a screen shot of the entire desktop, and saves it to a file/// < /summary> /// < param name="filename"> < /param> /// < param name="format"> < /param> public void CaptureScreenToFile(string filename, ImageFormat format){Image img = CaptureScreen(); img.Save(filename, format); }/// < 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); }}}

活动的Winform窗口截图使用完整的屏幕截图有两种方法, 使用带有Windows图形库的自实现屏幕截图或使用前面提到的类。
要仅从活动窗口中获取屏幕截图, 我们将使用以下类, 该类允许你执行不同类型的屏幕截图。
首先, 不要忘记在类顶部(你将在其中使用方法的地方)添加以下use语句, 以访问必要的方法：

using System.Drawing; using System.Drawing.Imaging;

现在, 要获取活动窗口的屏幕截图, 请在你的主类中使用以下方法：

/// < summary> /// Creates a screenshot of the active winform window./// It uses the ScreenCapture class./// < /summary> /// < param name="filepath"> < /param> /// < param name="filename"> < /param> /// < param name="format"> < /param> private void WindowScreenshot(String filepath, String filename, ImageFormat format){ScreenCapture sc = new ScreenCapture(); string fullpath = filepath + "\\" + filename; sc.CaptureWindowToFile(this.Handle, fullpath, format); }// Use like :WindowScreenshot(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "window_screenshot.jpg", ImageFormat.Jpeg);

现在另一种方法是使用.NET Graphics类中的CopyFromScreen方法。
使用以下方法无需任何类即可从活动窗口获取屏幕截图：

/// < summary> /// Take the screenshot of the active window using the CopyFromScreen method relative to the bounds of the form./// < /summary> /// < param name="filepath"> < /param> /// < param name="filename"> < /param> /// < param name="format"> < /param> private void WindowScreenshotWithoutClass(String filepath, String filename, ImageFormat format){Rectangle bounds = this.Bounds; using (Bitmap bitmap = new Bitmap(bounds.Width, bounds.Height)){using (Graphics g = Graphics.FromImage(bitmap)){g.CopyFromScreen(new Point(bounds.Left, bounds.Top), Point.Empty, bounds.Size); }string fullpath = filepath + "\\" + filename; bitmap.Save(fullpath, format); }}// Use it like : WindowScreenshotWithoutClass(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "window_screen_noclass.jpg", ImageFormat.Jpeg);

全屏截图使用完整的屏幕截图有两种方法, 使用带有Windows图形库的自实现屏幕截图或使用前面提到的类。
第一种方法采用全屏截图, 我们将使用.NET Graphics类中的CopyFromScreen方法。
首先, 不要忘记在类顶部添加以下use语句来访问必要的方法：

using System.Drawing; using System.Drawing.Imaging;

现在, 要截取屏幕截图并将其保存在指定目录中, 请使用以下方法：

/// < summary> /// Takes a fullscreen screenshot of the monitor and saves the specified file in a directory with custom name./// It expects the Format of the file./// < /summary> /// < param name="filepath"> < /param> /// < param name="filename"> < /param> /// < param name="format"> < /param> private void FullScreenshot(String filepath, String filename, ImageFormat format){Rectangle bounds = Screen.GetBounds(Point.Empty); using (Bitmap bitmap = new Bitmap(bounds.Width, bounds.Height)){using (Graphics g = Graphics.FromImage(bitmap)){g.CopyFromScreen(Point.Empty, Point.Empty, bounds.Size); }string fullpath = filepath + "\\" + filename; bitmap.Save(fullpath, format); }}// Use it as FullScreenshot(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "screenshot.jpg", ImageFormat.Jpeg);

并使用ScreenCapture类创建屏幕截图, 请使用以下方法：

/// < summary> ///Creates a screenshot using the ScreenCapture class./// < /summary> /// < param name="filepath"> < /param> /// < param name="filename"> < /param> /// < param name="format"> < /param> private void FullScreenshotWithClass(String filepath, String filename, ImageFormat format){ScreenCapture sc = new ScreenCapture(); Image img = sc.CaptureScreen(); string fullpath = filepath + "\\" + filename; img.Save(fullpath, format); }// And use it like FullScreenshotWithClass(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "screenshotfull_class.jpg", ImageFormat.Jpeg);

更多信息

请记住, 你可以更改扩展名和ImageFormat类型来更改图像的格式。此类支持以下格式：
- ImageFormat.Jpeg
- 图片格式
- ImageFormat.Tiff
- ImageFormat.Icon
- ImageFormat.MemoryBmp
- ImageFormat.Bmp
- ImageFormat.Exif

【使用C＃和Winforms捕获不同方式的屏幕截图】玩得开心。