.Net Core - copy to clipboard?

This project of mine (https://github.com/SimonCropp/TextCopy) uses a mixed approach of PInvoke and command line invocation. it currently supports

  • Windows with .NET Framework 4.6.1 and up
  • Windows with .NET Core 2.0 and up
  • Windows with Mono 5.0 and up
  • OSX with .NET Core 2.0 and up
  • OSX with Mono 5.20.1 and up
  • Linux with .NET Core 2.0 and up
  • Linux with Mono 5.20.1 and up

Usage:

Install-Package TextCopy

TextCopy.ClipboardService.SetText("Text to place in clipboard");

Or just use the actual code

Windows

https://github.com/CopyText/TextCopy/blob/master/src/TextCopy/WindowsClipboard.cs

static class WindowsClipboard
{
    public static void SetText(string text)
    {
        OpenClipboard();

        EmptyClipboard();
        IntPtr hGlobal = default;
        try
        {
            var bytes = (text.Length + 1) * 2;
            hGlobal = Marshal.AllocHGlobal(bytes);

            if (hGlobal == default)
            {
                ThrowWin32();
            }

            var target = GlobalLock(hGlobal);

            if (target == default)
            {
                ThrowWin32();
            }

            try
            {
                Marshal.Copy(text.ToCharArray(), 0, target, text.Length);
            }
            finally
            {
                GlobalUnlock(target);
            }

            if (SetClipboardData(cfUnicodeText, hGlobal) == default)
            {
                ThrowWin32();
            }

            hGlobal = default;
        }
        finally
        {
            if (hGlobal != default)
            {
                Marshal.FreeHGlobal(hGlobal);
            }

            CloseClipboard();
        }
    }

    public static void OpenClipboard()
    {
        var num = 10;
        while (true)
        {
            if (OpenClipboard(default))
            {
                break;
            }

            if (--num == 0)
            {
                ThrowWin32();
            }

            Thread.Sleep(100);
        }
    }

    const uint cfUnicodeText = 13;

    static void ThrowWin32()
    {
        throw new Win32Exception(Marshal.GetLastWin32Error());
    }

    [DllImport("kernel32.dll", SetLastError = true)]
    static extern IntPtr GlobalLock(IntPtr hMem);

    [DllImport("kernel32.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    static extern bool GlobalUnlock(IntPtr hMem);

    [DllImport("user32.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    static extern bool OpenClipboard(IntPtr hWndNewOwner);

    [DllImport("user32.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    static extern bool CloseClipboard();

    [DllImport("user32.dll", SetLastError = true)]
    static extern IntPtr SetClipboardData(uint uFormat, IntPtr data);

    [DllImport("user32.dll")]
    static extern bool EmptyClipboard();
}

macOS

https://github.com/CopyText/TextCopy/blob/master/src/TextCopy/OsxClipboard.cs

static class OsxClipboard
{
    public static void SetText(string text)
    {
        var nsString = objc_getClass("NSString");
        IntPtr str = default;
        IntPtr dataType = default;
        try
        {
            str = objc_msgSend(objc_msgSend(nsString, sel_registerName("alloc")), sel_registerName("initWithUTF8String:"), text);
            dataType = objc_msgSend(objc_msgSend(nsString, sel_registerName("alloc")), sel_registerName("initWithUTF8String:"), NSPasteboardTypeString);

            var nsPasteboard = objc_getClass("NSPasteboard");
            var generalPasteboard = objc_msgSend(nsPasteboard, sel_registerName("generalPasteboard"));

            objc_msgSend(generalPasteboard, sel_registerName("clearContents"));
            objc_msgSend(generalPasteboard, sel_registerName("setString:forType:"), str, dataType);
        }
        finally
        {
            if (str != default)
            {
                objc_msgSend(str, sel_registerName("release"));
            }

            if (dataType != default)
            {
                objc_msgSend(dataType, sel_registerName("release"));
            }
        }
    }

    [DllImport("/System/Library/Frameworks/AppKit.framework/AppKit")]
    static extern IntPtr objc_getClass(string className);

    [DllImport("/System/Library/Frameworks/AppKit.framework/AppKit")]
    static extern IntPtr objc_msgSend(IntPtr receiver, IntPtr selector);

    [DllImport("/System/Library/Frameworks/AppKit.framework/AppKit")]
    static extern IntPtr objc_msgSend(IntPtr receiver, IntPtr selector, string arg1);

    [DllImport("/System/Library/Frameworks/AppKit.framework/AppKit")]
    static extern IntPtr objc_msgSend(IntPtr receiver, IntPtr selector, IntPtr arg1, IntPtr arg2);

    [DllImport("/System/Library/Frameworks/AppKit.framework/AppKit")]
    static extern IntPtr sel_registerName(string selectorName);

    const string NSPasteboardTypeString = "public.utf8-plain-text";
}

Linux

https://github.com/CopyText/TextCopy/blob/master/src/TextCopy/LinuxClipboard_2.1.cs

static class LinuxClipboard
{
    public static void SetText(string text)
    {
        var tempFileName = Path.GetTempFileName();
        File.WriteAllText(tempFileName, text);
        try
        {
            BashRunner.Run($"cat {tempFileName} | xclip");
        }
        finally
        {
            File.Delete(tempFileName);
        }
    }

    public static string GetText()
    {
        var tempFileName = Path.GetTempFileName();
        try
        {
            BashRunner.Run($"xclip -o > {tempFileName}");
            return File.ReadAllText(tempFileName);
        }
        finally
        {
            File.Delete(tempFileName);
        }
    }
}

static class BashRunner
{
    public static string Run(string commandLine)
    {
        var errorBuilder = new StringBuilder();
        var outputBuilder = new StringBuilder();
        var arguments = $"-c \"{commandLine}\"";
        using (var process = new Process
        {
            StartInfo = new ProcessStartInfo
            {
                FileName = "bash",
                Arguments = arguments,
                RedirectStandardOutput = true,
                RedirectStandardError = true,
                UseShellExecute = false,
                CreateNoWindow = false,
            }
        })
        {
            process.Start();
            process.OutputDataReceived += (sender, args) => { outputBuilder.AppendLine(args.Data); };
            process.BeginOutputReadLine();
            process.ErrorDataReceived += (sender, args) => { errorBuilder.AppendLine(args.Data); };
            process.BeginErrorReadLine();
            if (!process.WaitForExit(500))
            {
                var timeoutError = $@"Process timed out. Command line: bash {arguments}.
Output: {outputBuilder}
Error: {errorBuilder}";
                throw new Exception(timeoutError);
            }
            if (process.ExitCode == 0)
            {
                return outputBuilder.ToString();
            }

            var error = $@"Could not execute process. Command line: bash {arguments}.
Output: {outputBuilder}
Error: {errorBuilder}";
            throw new Exception(error);
        }
    }
}

Clipboard class is missing, hope in near future will be add an option for that. While it happen ... you can run a native shell command with ProcessStartInfo.

I'm noob in Net Core, but create this code to send and string to clipboard on Windows and Mac:

OS Detection Class

public static class OperatingSystem
{
    public static bool IsWindows() =>
        RuntimeInformation.IsOSPlatform(OSPlatform.Windows);

    public static bool IsMacOS() =>
        RuntimeInformation.IsOSPlatform(OSPlatform.OSX);

    public static bool IsLinux() =>
        RuntimeInformation.IsOSPlatform(OSPlatform.Linux);
}

Shell Class
Based on https://loune.net/2017/06/running-shell-bash-commands-in-net-core/

public static class Shell
{
    public static string Bash(this string cmd)
    {
        var escapedArgs = cmd.Replace("\"", "\\\"");
        string result = Run("/bin/bash", $"-c \"{escapedArgs}\"");
        return result;
    }

    public static string Bat(this string cmd)
    {
        var escapedArgs = cmd.Replace("\"", "\\\"");
        string result = Run("cmd.exe", $"/c \"{escapedArgs}\"");
        return result;
    }

    private static string Run (string filename, string arguments){
        var process = new Process()
        {
            StartInfo = new ProcessStartInfo
            {
                FileName = filename,
                Arguments = arguments,
                RedirectStandardOutput = true,
                UseShellExecute = false,
                CreateNoWindow = false,
            }
        };
        process.Start();
        string result = process.StandardOutput.ReadToEnd();
        process.WaitForExit();
        return result;
    }
}

Clipboard Class

public static class Clipboard
{
    public static void Copy(string val)
    {
        if (OperatingSystem.IsWindows())
        {
            $"echo {val} | clip".Bat();
        }

        if (OperatingSystem.IsMacOS())
        {
            $"echo \"{val}\" | pbcopy".Bash();
        }
    }
}

Then Finally, you can call Clipboard Copy and can get the value on the clipboard.

var dirPath = @"C:\MyPath";
Clipboard.Copy(dirPath);

Hope it help others! Improvements are welcome.

I'm working in a ToolBox library for .net core with all this things: https://github.com/deinsoftware/toolbox (also available as NuGet Package).

Run a command in external terminal with .Net Core: https://dev.to/deinsoftware/run-a-command-in-external-terminal-with-net-core-d4l