I am coding away on my plugin for SDL Trados Studio.
The last part of the plugin requires some automation that is not exposed by the APIs at all, so all I have (hold on to something) is to automate the default keyboard shortcuts.
I have the code working perfectly for the English keyboard layout (and Hungarian, too!), but it of course does not work for Greek, Russian and so forth.
I have been searching for the solution but I was not able to find it until now, not on the web nor on SO, such as this post: Change keyboard layouts through code c#
I need to change the keyboard layout to English so it can take the correct shortcuts (and other character strings). Then I need to switch it back to what it was before. I am working with a very limited API, so I only have SendKeys at my disposal.
Here is the working code:
//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");
}
}
So the questions I have:
Can somebody help me with a code to actually store the current keyboard layout and switch to English, then switch it back at the end?
Is there a simpler solution? I tried to look at the native methods but it is too high for me, so I would really appreciate any help to convert my code into native if that is the way to go instead of switching the keyboard layout. Any suggestions?
Switching the keyboard layout requires some P/Invoke; you´ll need at least the following Windows functions to get it working: LoadKeyboardLayout, GetKeyboardLayout and ActivateKeyboardLayout. The following import declarations worked for me...
[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;
}
Whenever I have to use native API methods I try to encapsulate them in a class that hides their declaration from the rest of the project´s codebase. So, I came up with a class called KeyboardLayout; that class can load and activate a layout by a given CultureInfo, which comes in handy...
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);
}
}
If you only need to have the layout be active for a short while - and you want make sure to properly restore the layout when done, you could write some kind of a scope type using the IDiposable interface. For instance...
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();
}
}
Than you can use it like this...
const int English = 1033;
using (new KeyboardLayoutScope(CultureInfo.GetCultureInfo(English))
{
// the layout will be valid within this using-block
}
You should know that in newer versions of Windows (beginning in Windows 8) the keyboard layout cannot be set for a certain process anymore, instead it is set globally for the entire system - and the layout can also be changed by other applications, or by the user (using the Win + Spacebar shortcut).
I would also recommend to not use SendKeys (or its native counterpart SendInput) since it simulates keyboard input which will be routed to the active/focused window. Using the SendMessage function instead is suitable, but you might want combine that with functionality that can properly determine the target window; but to explain such technique would go beyond the scope of the this question and answer. This answer here illustrates a possible solution: How to send keystrokes to a window?