logo标签列表

如何捕获活动窗口的屏幕截图？

c#screenshotactive-window
205

我正在开发一个屏幕截图应用程序，一切进展顺利。我只需要捕获活动窗口并对此活动窗口进行截屏即可。请问有人知道如何实现吗？

18
“Active window”是指你的应用程序中当前处于活动状态的窗口，而不是如果你的应用程序被隐藏后将会处于活动状态的窗口。 - Corey Trager
1
如果您想要所有显示器的屏幕截图：https://dev59.com/cGUo5IYBdhLWcg3wrhFD - VDWWD
13个回答
251
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);
    }
    bitmap.Save("test.jpg", ImageFormat.Jpeg);
}

用于捕获当前窗口的方法：

 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);
    }
    bitmap.Save("C://test.jpg", ImageFormat.Jpeg);
 }
你好，我可以知道如何在VB Web表单aspx中进行屏幕截图吗？ - beny lim
嗨@benylim，看一下这个(https://dev59.com/aXRB5IYBdhLWcg3wJklC)和这个(http://social.msdn.microsoft.com/Forums/en/netfxjscript/thread/e64c562d-20cd-43b1-b13f-b12f09969619)，希望能够帮到你。 - Arsen Mkrtchyan
我认为没有不使用js或ActivX的方法来实现这个。 - Arsen Mkrtchyan
哦，因为我不是很理解它。 - beny lim
这个代码可以运行，但是生成的图像有点太大了。例如，如果我的窗体是全屏的，我会在所有边缘上留下一些黑色边框，而 form.Bounds.Location 给出的是 (-8, -8) 而不是 (0, 0)。 - user276648
显示剩余5条评论
161
ScreenCapture sc = new ScreenCapture();
// capture entire screen, and save it to a file
Image img = sc.CaptureScreen();
// display image in a Picture control named imageDisplay
this.imageDisplay.Image = img;
// capture this window, and save it
sc.CaptureWindowToFile(this.Handle,"C:\\temp2.gif",ImageFormat.Gif);

http://www.developerfusion.com/code/4630/capture-a-screen-shot/

7
我已经知道如何截取标准截屏。我只需要知道如何截取活动窗口。 - user
6
尝试运行以上代码时，我遇到了GDI+错误。该错误发生在ScreenCapture类保存图片时发生。 - hurnhu
2
太好了！我想在我的应用程序中捕获一个面板的内容。所以我使用了 sc.CaptureWindowToFile(panel1.Handle, "c:\temp.jpg", imageformat.jpg) ，然后就完成了！ - D. Kermott
2
在高清分辨率下，Windows界面元素被放大的情况下，这个类无法捕获整个屏幕。 - Yeronimo
4
屏幕截图功能仅支持运行 Windows Phone 8.1 的移动设备。该 API 不支持 Windows 10。 - Naresh Ravlani
显示剩余5条评论
33

这里是一个捕获桌面或活动窗口的代码片段，它不涉及Windows Forms。

public class ScreenCapture
{
    [DllImport("user32.dll")]
    private static extern IntPtr GetForegroundWindow();

    [DllImport("user32.dll", CharSet = CharSet.Auto, ExactSpelling = true)]
    public static extern IntPtr GetDesktopWindow();

    [StructLayout(LayoutKind.Sequential)]
    private struct Rect
    {
        public int Left;
        public int Top;
        public int Right;
        public int Bottom;
    }   

    [DllImport("user32.dll")]
    private static extern IntPtr GetWindowRect(IntPtr hWnd, ref Rect rect);

    public static Image CaptureDesktop()
    {
        return CaptureWindow(GetDesktopWindow());
    }

    public static Bitmap CaptureActiveWindow()
    {
        return CaptureWindow(GetForegroundWindow());
    }

    public static Bitmap CaptureWindow(IntPtr handle)
    {
        var rect = new Rect();
        GetWindowRect(handle, ref rect);
        var bounds = new Rectangle(rect.Left, rect.Top, rect.Right - rect.Left, rect.Bottom - rect.Top);
        var result = new Bitmap(bounds.Width, bounds.Height);

        using (var graphics = Graphics.FromImage(result))
        {
            graphics.CopyFromScreen(new Point(bounds.Left, bounds.Top), Point.Empty, bounds.Size);
        }

        return result;
    }
}

如何捕获整个屏幕：

var image = ScreenCapture.CaptureDesktop();
image.Save(@"C:\temp\snippetsource.jpg", ImageFormat.Jpeg);

如何捕获活动窗口：

var image = ScreenCapture.CaptureActiveWindow();
image.Save(@"C:\temp\snippetsource.jpg", ImageFormat.Jpeg);

最初的来源在这里：http://www.snippetsource.net/Snippet/158/capture-screenshot-in-c

非常感谢Christian提供这个很棒的代码片段。它对我帮助很大！ - casaout
2
这个很好用，但如果用户在该显示器上设置了缩放（即125％会切掉左侧和底部），则无法正常工作。 - russelrillema
需要使用库 System.Drawing.Common。 - user2347921
31

我建议使用以下方案来捕获任何当前活动窗口（不仅限于我们的C#应用程序）或整个屏幕，并确定光标位置相对于窗口或屏幕左上角的位置：

public enum enmScreenCaptureMode
{
    Screen,
    Window
}

class ScreenCapturer
{
    [DllImport("user32.dll")]
    private static extern IntPtr GetForegroundWindow();

    [DllImport("user32.dll")]
    private static extern IntPtr GetWindowRect(IntPtr hWnd, ref Rect rect);

    [StructLayout(LayoutKind.Sequential)]
    private struct Rect
    {
        public int Left;
        public int Top;
        public int Right;
        public int Bottom;
    }

    public Bitmap Capture(enmScreenCaptureMode screenCaptureMode = enmScreenCaptureMode.Window)
    {
        Rectangle bounds;

        if (screenCaptureMode == enmScreenCaptureMode.Screen)
        {
            bounds = Screen.GetBounds(Point.Empty);
            CursorPosition = Cursor.Position;
        }
        else
        {
            var foregroundWindowsHandle = GetForegroundWindow();
            var rect = new Rect();
            GetWindowRect(foregroundWindowsHandle, ref rect);
            bounds = new Rectangle(rect.Left, rect.Top, rect.Right - rect.Left, rect.Bottom - rect.Top);
            CursorPosition = new Point(Cursor.Position.X - rect.Left, Cursor.Position.Y - rect.Top);
        }

        var result = new Bitmap(bounds.Width, bounds.Height);

        using (var g = Graphics.FromImage(result))
        {
            g.CopyFromScreen(new Point(bounds.Left, bounds.Top), Point.Empty, bounds.Size);
        }

        return result;
    }

    public Point CursorPosition
    {
        get;
        protected set;
    }
}
我们为什么需要声明自己的矩形结构，而不使用 System.Drawing.Rectangle？这只是为了添加属性吗？您是否知道我们是否应该对 Point 结构执行此操作？ - Caster Troy
@Alex，我试图用System Rectangle替换我的Rect，但是在那之后，函数GetWindowRect返回了错误的矩形。它设置了输出矩形的Width和Height，而不是Right和Top。 - Ivan Kochurkin
1
一个注意事项：前台窗口并不一定是从中调用此函数的应用程序的窗口。对于单个窗口 WPF 应用程序，您需要使用 var thisWindowHandle = new WindowInteropHelper(Application.Current.MainWindow).Handle;。 - stijn
13

KvanTTT的代码很好用。我稍微扩展了一下，让它在保存格式上更加灵活，同时还能够按照hWnd，.NET控件/窗体进行保存。你可以得到一个位图或保存到文件，并具有一些选项。

using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace MosaiqPerformanceMonitor {
     public enum CaptureMode {
          Screen, Window
     }

     public static class ScreenCapturer {
          [DllImport("user32.dll")]
          private static extern IntPtr GetForegroundWindow();

          [DllImport("user32.dll")]
          private static extern IntPtr GetWindowRect(IntPtr hWnd, ref Rect rect);

          [StructLayout(LayoutKind.Sequential)]
          private struct Rect {
                public int Left;
                public int Top;
                public int Right;
                public int Bottom;
          }

          [DllImport("user32.dll", CharSet = CharSet.Auto, ExactSpelling = true)]
          public static extern IntPtr GetDesktopWindow();

          /// <summary> Capture Active Window, Desktop, Window or Control by hWnd or .NET Contro/Form and save it to a specified file.  </summary>
          /// <param name="filename">Filename.
          /// <para>* If extension is omitted, it's calculated from the type of file</para>
          /// <para>* If path is omitted, defaults to %TEMP%</para>
          /// <para>* Use %NOW% to put a timestamp in the filename</para></param>
          /// <param name="mode">Optional. The default value is CaptureMode.Window.</param>
          /// <param name="format">Optional file save mode.  Default is PNG</param>
          public static void CaptureAndSave(string filename, CaptureMode mode = CaptureMode.Window, ImageFormat format = null) {
                ImageSave(filename, format, Capture(mode));
          }

          /// <summary> Capture a specific window (or control) and save it to a specified file.  </summary>
          /// <param name="filename">Filename.
          /// <para>* If extension is omitted, it's calculated from the type of file</para>
          /// <para>* If path is omitted, defaults to %TEMP%</para>
          /// <para>* Use %NOW% to put a timestamp in the filename</para></param>
          /// <param name="handle">hWnd (handle) of the window to capture</param>
          /// <param name="format">Optional file save mode.  Default is PNG</param>
          public static void CaptureAndSave(string filename, IntPtr handle, ImageFormat format = null) {
                ImageSave(filename, format, Capture(handle));
          }

          /// <summary> Capture a specific window (or control) and save it to a specified file.  </summary>
          /// <param name="filename">Filename.
          /// <para>* If extension is omitted, it's calculated from the type of file</para>
          /// <para>* If path is omitted, defaults to %TEMP%</para>
          /// <para>* Use %NOW% to put a timestamp in the filename</para></param>
          /// <param name="c">Object to capture</param>
          /// <param name="format">Optional file save mode.  Default is PNG</param>
          public static void CaptureAndSave(string filename, Control c, ImageFormat format = null) {
                ImageSave(filename, format, Capture(c));
          }
          /// <summary> Capture the active window (default) or the desktop and return it as a bitmap </summary>
          /// <param name="mode">Optional. The default value is CaptureMode.Window.</param>
          public static Bitmap Capture(CaptureMode mode = CaptureMode.Window) {
                return Capture(mode == CaptureMode.Screen ? GetDesktopWindow() : GetForegroundWindow());
          }

          /// <summary> Capture a .NET Control, Form, UserControl, etc. </summary>
          /// <param name="c">Object to capture</param>
          /// <returns> Bitmap of control's area </returns>
          public static Bitmap Capture(Control c) {
                return Capture(c.Handle);
          }


          /// <summary> Capture a specific window and return it as a bitmap </summary>
          /// <param name="handle">hWnd (handle) of the window to capture</param>
          public static Bitmap Capture(IntPtr handle) {
                Rectangle bounds;
                var rect = new Rect();
                GetWindowRect(handle, ref rect);
                bounds = new Rectangle(rect.Left, rect.Top, rect.Right - rect.Left, rect.Bottom - rect.Top);
                CursorPosition = new Point(Cursor.Position.X - rect.Left, Cursor.Position.Y - rect.Top);

                var result = new Bitmap(bounds.Width, bounds.Height);
                using (var g = Graphics.FromImage(result))
                     g.CopyFromScreen(new Point(bounds.Left, bounds.Top), Point.Empty, bounds.Size);

                return result;
          }

          /// <summary> Position of the cursor relative to the start of the capture </summary>
          public static Point CursorPosition;


          /// <summary> Save an image to a specific file </summary>
          /// <param name="filename">Filename.
          /// <para>* If extension is omitted, it's calculated from the type of file</para>
          /// <para>* If path is omitted, defaults to %TEMP%</para>
          /// <para>* Use %NOW% to put a timestamp in the filename</para></param>
          /// <param name="format">Optional file save mode.  Default is PNG</param>
          /// <param name="image">Image to save.  Usually a BitMap, but can be any
          /// Image.</param>
          static void ImageSave(string filename, ImageFormat format, Image image) {
                format = format ?? ImageFormat.Png;
                if (!filename.Contains("."))
                     filename = filename.Trim() + "." + format.ToString().ToLower();

                if (!filename.Contains(@"\"))
                     filename = Path.Combine(Environment.GetEnvironmentVariable("TEMP") ?? @"C:\Temp", filename);

                filename = filename.Replace("%NOW%", DateTime.Now.ToString("yyyy-MM-dd@hh.mm.ss"));
                image.Save(filename, format);
          }
     }
}
代码的前面部分，已经顺利地运行了，正是我所需要的。感谢您的分享。 - Hugo Yates
7
5
3
如果您想使用托管代码：这将通过 ProcessId 捕获任何窗口。
我使用以下代码使窗口处于活动状态。
Microsoft.VisualBasic.Interaction.AppActivate(ProcessId);
Threading.Thread.Sleep(20);

我使用打印屏幕功能来截取窗口。
SendKeys.SendWait("%{PRTSC}");
Threading.Thread.Sleep(40);
IDataObject objData = Clipboard.GetDataObject();
2
请使用以下代码：
            // Shot size = screen size
            Size shotSize = Screen.PrimaryScreen.Bounds.Size;

            // the upper left point in the screen to start shot
            // 0,0 to get the shot from upper left point
            Point upperScreenPoint = new Point(0, 0);

            // the upper left point in the image to put the shot
            Point upperDestinationPoint = new Point(0, 0);

            // create image to get the shot in it
            Bitmap shot = new Bitmap(shotSize.Width, shotSize.Height);

            // new Graphics instance 
            Graphics graphics = Graphics.FromImage(shot);

            // get the shot by Graphics class 
            graphics.CopyFromScreen(upperScreenPoint, upperDestinationPoint, shotSize);

            // return the image
            pictureBox1.Image = shot;
2

如果桌面缩放设置正确，此功能可正常工作。

public class ScreenCapture
{
    [DllImport("user32.dll")]
    private static extern IntPtr GetForegroundWindow();

    [DllImport("user32.dll", CharSet = CharSet.Auto, ExactSpelling = true)]
    public static extern IntPtr GetDesktopWindow();

    [StructLayout(LayoutKind.Sequential)]
    private struct Rect
    {
        public int Left;
        public int Top;
        public int Right;
        public int Bottom;
    }

    [DllImport("user32.dll")]
    private static extern IntPtr GetWindowRect(IntPtr hWnd, ref Rect rect);

    public static Image CaptureDesktop()
    {
        return CaptureWindow(GetDesktopWindow());
    }

    public static Bitmap CaptureActiveWindow()
    {
        return CaptureWindow(GetForegroundWindow());
    }

    public static Bitmap CaptureWindow(IntPtr handle)
    {
        var rect = new Rect();
        GetWindowRect(handle, ref rect);
        GetScale getScale = new GetScale();
        var bounds = new Rectangle(rect.Left, rect.Top, (int)((rect.Right - rect.Left)* getScale.getScalingFactor()), (int)((rect.Bottom - rect.Top )* getScale.getScalingFactor()));
        var result = new Bitmap(bounds.Width, bounds.Height);

        using (var graphics = Graphics.FromImage(result))
        {
            graphics.CopyFromScreen(new Point(bounds.Left, bounds.Top), Point.Empty, bounds.Size);
        }

        return result;
    }
}
在截图之前，代码将检查是否设置了缩放。如果设置，则因子将与矩形的高度和宽度相乘。 - Krishnaraj k
9
似乎缺少 GetScale 类。 - Guillermo Prandi
网页内容由stack overflow 提供, 点击上面的
可以查看英文原文，
原文链接