使用 .NET 4.5.2 从 C# 代码更改键盘布局答案

【问题标题】：Change keyboard layout from C# code with .NET 4.5.2使用 .NET 4.5.2 从 C# 代码更改键盘布局
【发布时间】：2016-05-18 06:07:31
【问题描述】：

我正在编写我的 SDL Trados Studio 插件。

插件的最后一部分需要一些 API 根本没有公开的自动化，所以我所拥有的（坚持一些事情）就是自动化默认的键盘快捷键。

我的代码非常适合英语键盘布局（还有匈牙利语！），但它当然不适用于希腊语、俄语等。

我一直在寻找解决方案，但直到现在我都无法找到它，不是在网络上也不是在 SO 上，例如这个帖子：Change keyboard layouts through code c#

我需要将键盘布局更改为英文，以便它可以使用正确的快捷键（和其他字符串）。然后我需要将其切换回以前的状态。我正在使用非常有限的 API，所以我只能使用 SendKeys。

这是工作代码：

//Save the document
SendKeys.SendWait("^s");
//Open files view
SendKeys.SendWait("%v");

SendKeys.SendWait("i");
SendKeys.SendWait("1");
Application.DoEvents();

//get url and credentials from a custom input form
string[] psw = UploadData.GetPassword(
    Settings.GetValue("Upload", "Uri", ""), 
    Vars.wsUsername == null ? Settings.GetValue("Upload", "User", "") : Vars.wsUsername, 
    Vars.wsPassword == null ? "" : Vars.wsPassword
    );
Application.DoEvents();

if (psw != null)
{
    try
    {
        //start upload
        SendKeys.SendWait("%h");
        SendKeys.Send("r");

        //select all files
        SendKeys.Send("%a");
        SendKeys.Send("%n");
        //enter login url
        SendKeys.Send("%l");
        SendKeys.Send("{TAB}");
        SendKeys.Send(psw[0]);
        SendKeys.Send("{TAB}");
        SendKeys.Send("{ENTER}");

        //enter username
        SendKeys.Send("%l");
        SendKeys.Send("+{END}");
        SendKeys.Send(psw[1]);
        //enter credentials
        SendKeys.Send("%p");
        SendKeys.Send(SendEscape(psw[2]));
        SendKeys.Send("{ENTER}");
        //start upload
        SendKeys.SendWait("%f");
    }
    catch (Exception)
    {
        MessageBox.Show("Cannot do automatic upload, please use the default method of Trados Studio.", "Error", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
    }
    finally
    {
        //switch back to editor view
        SendKeys.SendWait("%vd");
    }
}

所以我的问题是：

谁能帮我写一个代码来实际存储当前的键盘布局并切换到英文，然后在最后切换回来？
有没有更简单的解决方案？我试图查看本机方法，但它对我来说太高了，所以如果这是代替切换键盘布局的方法，我将非常感谢将我的代码转换为本机的任何帮助。有什么建议吗？

【问题讨论】：

标签： c# .net keyboard pinvoke sendkeys

【解决方案1】：

切换键盘布局需要一些 P/Invoke；您至少需要以下 Windows 功能才能使其正常工作：LoadKeyboardLayout、GetKeyboardLayout 和 ActivateKeyboardLayout。以下导入声明对我有用...

[DllImport("user32.dll", 
    CallingConvention = CallingConvention.StdCall, 
    CharSet = CharSet.Unicode, 
    EntryPoint = "LoadKeyboardLayout", 
    SetLastError = true, 
    ThrowOnUnmappableChar = false)]
static extern uint LoadKeyboardLayout(
    StringBuilder pwszKLID, 
    uint flags);

[DllImport("user32.dll", 
    CallingConvention = CallingConvention.StdCall,
    CharSet = CharSet.Unicode, 
    EntryPoint = "GetKeyboardLayout", 
    SetLastError = true, 
    ThrowOnUnmappableChar = false)]
static extern uint GetKeyboardLayout(
    uint idThread);

[DllImport("user32.dll", 
    CallingConvention = CallingConvention.StdCall, 
    CharSet = CharSet.Unicode, 
    EntryPoint = "ActivateKeyboardLayout", 
    SetLastError = true, 
    ThrowOnUnmappableChar = false)]
static extern uint ActivateKeyboardLayout(
    uint hkl,
    uint Flags);

static class KeyboardLayoutFlags
{
    public const uint KLF_ACTIVATE = 0x00000001;
    public const uint KLF_SETFORPROCESS = 0x00000100;
}

每当我必须使用本机 API 方法时，我都会尝试将它们封装在一个类中，从而将它们的声明隐藏在项目代码库的其余部分中。所以，我想出了一个名为KeyboardLayout的类；该类可以通过给定的CultureInfo 加载和激活布局，这很方便......

internal sealed class KeyboardLayout
{
    ...

    private readonly uint hkl;

    private KeyboardLayout(CultureInfo cultureInfo)
    {
        string layoutName = cultureInfo.LCID.ToString("x8");

        var pwszKlid = new StringBuilder(layoutName);
        this.hkl = LoadKeyboardLayout(pwszKlid, KeyboardLayoutFlags.KLF_ACTIVATE);
    }

    private KeyboardLayout(uint hkl)
    {
        this.hkl = hkl;
    }

    public uint Handle
    {
        get
        {
            return this.hkl;
        }
    }

    public static KeyboardLayout GetCurrent()
    {
        uint hkl = GetKeyboardLayout((uint)Thread.CurrentThread.ManagedThreadId);
        return new KeyboardLayout(hkl);
    }

    public static KeyboardLayout Load(CultureInfo culture)
    {
        return new KeyboardLayout(culture);
    }

    public void Activate()
    {
        ActivateKeyboardLayout(this.hkl, KeyboardLayoutFlags.KLF_SETFORPROCESS);
    }
}

如果您只需要让布局在短时间内处于活动状态 - 并且您希望确保在完成后正确恢复布局，您可以使用IDiposable 接口编写某种范围类型。比如……

class KeyboardLayoutScope : IDiposable
{
    private readonly KeyboardLayout currentLayout;

    public KeyboardLayoutScope(CultureInfo culture)
    {
        this.currentLayout = KeyboardLayout.GetCurrent();
        var layout = KeyboardLayout.Load(culture);
        layout.Activate();
    }

    public void Dispose()
    {
        this.currentLayout.Activate();
    }
}

比你可以这样使用它......

const int English = 1033;
using (new KeyboardLayoutScope(CultureInfo.GetCultureInfo(English))
{
    // the layout will be valid within this using-block
}

您应该知道，在较新版本的 Windows 中（从 Windows 8 开始），键盘布局不能再为某个进程设置，而是为整个系统全局设置 - 布局也可以由其他应用程序更改，或由用户（使用 Win + Spacebar 快捷方式）。

我还建议不要使用SendKeys（或其本机对应物SendInput），因为它模拟键盘输入，将路由到活动/聚焦窗口。改用SendMessage 函数是合适的，但您可能希望将其与可以正确确定目标窗口的功能结合起来；但解释这种技术将超出本问答的范围。这里的答案说明了一个可能的解决方案：How to send keystrokes to a window?

【讨论】：

【解决方案2】：

更改类@Matze，

internal class KeyboardLayoutScope : IDisposable, IKeyboardLayoutScope
    {
        private readonly KeyboardLayout currentLayout;

        public KeyboardLayoutScope() { }

        public KeyboardLayoutScope(CultureInfo culture)
        {
            currentLayout = KeyboardLayout.GetCurrent();
            KeyboardLayout.Load(culture).Activate();
        }

        public KeyboardLayoutScope(KeyboardLayout currentLayout) => this.currentLayout = currentLayout;

        public void Dispose() => currentLayout.Activate();
    }
    internal interface IKeyboardLayoutScope
    {
        void Dispose();
    }

其他类

internal sealed class KeyboardLayout
    {
        private readonly uint hkl;

        private KeyboardLayout(CultureInfo cultureInfo) => hkl = NativeMethods.LoadKeyboardLayout(new StringBuilder(cultureInfo.LCID.ToString("x8")), KeyboardLayoutFlags.KLF_ACTIVATE);

        private KeyboardLayout(uint hkl) => this.hkl = hkl;

        public uint Handle => hkl;

        public static KeyboardLayout GetCurrent() => new KeyboardLayout(NativeMethods.GetKeyboardLayout((uint)Thread.CurrentThread.ManagedThreadId));

        public static KeyboardLayout Load(CultureInfo culture) => new KeyboardLayout(culture);

        public void Activate() => NativeMethods.ActivateKeyboardLayout(hkl, KeyboardLayoutFlags.KLF_SETFORPROCESS);
    }

【讨论】：

NativeMethods.LoadKeyboardLayout 在哪里？

【解决方案3】：

试试这个：

        public void switch_keyboard(string lang)
    {
        string keyboard_lang = InputLanguage.CurrentInputLanguage.Culture.TwoLetterISOLanguageName;
        if (keyboard_lang != lang) 
        {
            int en_index = -1;
            for (int i = 0; i < System.Windows.Forms.InputLanguage.InstalledInputLanguages.Count - 1; i++)
            {
                try  
                {
                    if (System.Windows.Forms.InputLanguage.InstalledInputLanguages[i].Culture.TwoLetterISOLanguageName == lang)
                    { en_index = i;  break; }
                }
                catch { break; }
            }
            if (en_index != -1)
            { InputLanguage.CurrentInputLanguage = System.Windows.Forms.InputLanguage.InstalledInputLanguages[en_index]; }
        }
    }

【讨论】：

用法：switch_keyboard("en")

【解决方案4】：

通过c#代码改变键盘布局：

using System;
using System.Linq;
using System.Globalization;
using System.Windows.Forms;
...
public static void Switch_keyboard(string lang)
{
    CultureInfo cultureInfo = CultureInfo.CreateSpecificCulture(lang);
    InputLanguage inputLanguage = InputLanguage.FromCulture(cultureInfo);
    InputLanguage.CurrentInputLanguage = inputLanguage;
}

private void button1_Click(object sender, EventArgs e)
{
    var list = InputLanguage.InstalledInputLanguages.Cast<InputLanguage>().Select(c => c.Culture.Name).ToList(); 
    Switch_keyboard(list[0]); // "ru-RU" or "ru-BY" ...
}

【讨论】：

【解决方案5】：

在 4.6.1 中，此处发布的所有方法都无法正常工作> 我得到了解决方案：

// set keyboard layout
LoadKeyboardLayout("en-EN", 0x00000100);
// methods
[DllImport("user32.dll")] public static extern IntPtr GetKeyboardLayout(uint thread);
        [DllImport("user32.dll")]
        public static extern long LoadKeyboardLayout(
            string pwszKLID,  // input locale identifier
            uint Flags         // input locale identifier options
        );
    public static CultureInfo GetCurrentKeyboardLayout()
        {
            try
            {
                int keyboardLayout = GetKeyboardLayout(0).ToInt32() & 0xFFFF;
                return new CultureInfo(keyboardLayout);
            }
            catch
            {
                return new CultureInfo(1033); // Assume English if something went wrong.
            }
        }

【讨论】：