Question

我正在尝试保存windows 7上所有打开窗口的屏幕截图。

问题是，它不是获取打开窗口的屏幕截图，而是给我cmd.exe屏幕截图。（例如，不是采用谷歌浏览器截图，而是显示黑色cmd.exe截图）。

之前我在Windows 10上尝试过相同的代码，它似乎正在运行。

我使用http://www.developerfusion.com/code/4630/capture-a-screen-shot/中的以下代码来获取特定窗口的屏幕截图。

namespace ScreenShotDemo
{
    /// <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 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;

            User32.WINDOWINFO info = new User32.WINDOWINFO();
            User32.GetWindowInfo(handle, ref info);
            int width = info.rcWindow.right - info.rcWindow.left;
            int height = info.rcWindow.bottom - info.rcWindow.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>
        /// 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);

            [DllImport("user32.dll")]
            public static extern bool GetWindowInfo(IntPtr hwnd, ref WINDOWINFO pwi);

            [StructLayout(LayoutKind.Sequential)]
            public struct WINDOWINFO
            {
                public uint cbSize;
                public RECT rcWindow;
                public RECT rcClient;
                public uint dwStyle;
                public uint dwExStyle;
                public uint dwWindowStatus;
                public uint cxWindowBorders;
                public uint cyWindowBorders;
                public ushort atomWindowType;
                public ushort wCreatorVersion;

                public WINDOWINFO(Boolean? filler)
                 : this()   // Allows automatic initialization of "cbSize" with "new WINDOWINFO(null/true/false)".
                {
                    cbSize = (UInt32)(Marshal.SizeOf(typeof(WINDOWINFO)));
                }

            }

        }
    }
}

要获取我正在使用以下代码的打开窗口列表。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;

using HWND = System.IntPtr;

/// <summary>Contains functionality to get all the open windows.</summary>
public static class OpenWindowGetter
{
    /// <summary>Returns a dictionary that contains the handle and title of all the open windows.</summary>
    /// <returns>A dictionary that contains the handle and title of all the open windows.</returns>
    public static IDictionary<HWND, string> GetOpenWindows()
    {
        HWND shellWindow = GetShellWindow();
        Dictionary<HWND, string> windows = new Dictionary<HWND, string>();

        EnumWindows(delegate (HWND hWnd, int lParam)
        {
            if (hWnd == shellWindow) return true;
            if (!IsWindowVisible(hWnd)) return true;

            int length = GetWindowTextLength(hWnd);
            if (length == 0) return true;

            StringBuilder builder = new StringBuilder(length);
            GetWindowText(hWnd, builder, length + 1);

            windows[hWnd] = builder.ToString();
            return true;

        }, 0);

        return windows;
    }

    private delegate bool EnumWindowsProc(HWND hWnd, int lParam);

    [DllImport("USER32.DLL")]
    private static extern bool EnumWindows(EnumWindowsProc enumFunc, int lParam);

    [DllImport("USER32.DLL")]
    private static extern int GetWindowText(HWND hWnd, StringBuilder lpString, int nMaxCount);

    [DllImport("USER32.DLL")]
    private static extern int GetWindowTextLength(HWND hWnd);

    [DllImport("USER32.DLL")]
    private static extern bool IsWindowVisible(HWND hWnd);

    [DllImport("USER32.DLL")]
    private static extern IntPtr GetShellWindow();
}

以下是Main类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using ScreenShotDemo;
using System.Drawing.Imaging;

namespace ScreenCaptureTest
{
    class Program
    {
        static void Main(string[] args)
        {
            long start = DateTime.Now.Millisecond;
            captureAllWindowsToFile();
            //captureAllWindowsToFile2();
            //captureDesktopToFile();
            long end = DateTime.Now.Millisecond;

            Console.WriteLine("time taken: " + (end - start));
            //Console.Read();
        }

        static void captureAllWindowsToFile()
        {
            IDictionary<IntPtr, string> windowDict = OpenWindowGetter.GetOpenWindows();

            ScreenCapture sc = new ScreenCapture();
            int captureI = 0;
            string message = "";
            foreach(KeyValuePair<IntPtr, string> window in windowDict)
            {
                string imageName = "test" + ++captureI + ".jpg";
                message +=imageName + " : " + window.Value + "\n";
                sc.CaptureWindowToFile(window.Key, imageName, ImageFormat.Jpeg);
            }
            Console.WriteLine(message);
        }

        static void captureDesktopToFile()
        {
            ScreenCapture sc = new ScreenCapture();
            sc.CaptureScreenToFile("current.jpg", ImageFormat.Jpeg);
        }
    }
}

感谢任何帮助。

Answer 1

我终于找到了这个问题。

我更改了Windows 7设置以获得最佳性能，一旦我将其更改为正常的Aero设置。它按预期工作。

所有打开的窗口的屏幕截图

1 个答案: