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Update input language of on screen keyboard

I have an Windows Forms application written in C# .NET 5 with a webview2 control which hosts a kiosk based application which will be run full screen on a touchscreen.
The application will use the on screen keyboard for user input. The application is hosted on our own machines, which will only be used for our application so changing the system input language is exactly what we want to achieve.
I need to allow the users to pick their own input language. In 4.7.2 I can achieve this by setting InputLanguage.CurrentInputLanguage, which dynamically updates the on screen keyboard input language, you also see the system input language update in the task bar (which in production will not be visible to users).
In .NET 5, setting the same value does not have the desired effect, the on screen keyboard does not reflect the changed input language, not does the input language update in the taskbar.
I notice the libraries behind the scenes have changed which is clearly why I am having this issue.
I have tried the following without success in a simple dummy app:
private void btnEnglish_Click(object sender, EventArgs e)
{
var language = InputLanguage.FromCulture(System.Globalization.CultureInfo.GetCultureInfo("en-GB"));
if (InputLanguage.InstalledInputLanguages.IndexOf(language) >= 0)
InputLanguage.CurrentInputLanguage = language;
ChangeSystemInputLanguage(language);
}
private static void ChangeSystemInputLanguage(InputLanguage language)
{
Application.OleRequired();
IntPtr handleOld = ActivateKeyboardLayout(new HandleRef(language, language.Handle), 0);
if (handleOld == IntPtr.Zero)
{
throw new ArgumentException("ErrorBadInputLanguage", nameof(language));
}
}
[DllImport("user32.dll", CharSet = CharSet.Auto)]
public static extern IntPtr ActivateKeyboardLayout(HandleRef hkl, int uFlags);
Short of downgrading to 4.7.2 or re-writting in WPF (and such using the InputLanguageManager), can anyone make any recommendations how I might achieve the desired effect in .NET 5.0?

For anyone having this issue, the answer was incredibly simple...
before updating the CurrentInputLanguage, set focus on a control on in your form!

How do I arrange or sort the desktop icons in c#?

You know when you right-click the desktop and there's a "Sort by" option that allows you to sort the icons by "Name", "Size", "Item Type", or "Date Modified"? Well, I want to find a way to sort the desktop's icons with a push of a button.
I saw a similar question being asked here on stackoverflow but it's old and the code didn't work for me. The link to the question is: Arranging desktop icons with C# . I'm trying to achieve this in Windows 10.
There was a comment on there that said that the LVM_* and LVA_* values are stored in the commctrl.h file which comes with the SDK. I couldn't find that file for some reason.
Here's what i'm using:
//sort desktop
public const int LVM_ARRANGE = 4118;
public const int LVM_ALIGNLEFT = 1;
[DllImport("user32.dll", CharSet = CharSet.Auto)]
public static extern IntPtr GetDesktopWindow();
[DllImport("user32.dll")]
public static extern int SendMessage(IntPtr hWnd, uint Msg, int wParam, int lParam);
//end of sort desktop
private void organizeBtn_Click(object sender, EventArgs e)
{
var DesktopHandle = GetDesktopWindow();
MessageBox.Show(GetDesktopWindow().ToString());
SendMessage(GetDesktopWindow(), LVM_ARRANGE, LVM_ALIGNLEFT, 0);
}
I've been digging for info or some sort of direction about this topic, especially regarding windows 10, but I can't find much. Please help?

In Windows 10, the desktop (not tile world!) is still a SysListView32, but the GetDesktopWindow API call will return the handle of its grandparent, a Progman window - reminiscence of the ancient "Program Manager" of Windows 3.0. Then there is a shim of the SHELLDLL_DefView class, and below that you find buried the listview you're after.
Use the information from this answer to move down from the shell window to the folder view, which you can eventually send the LVM_ARRANGE message.
This is a brittle approach, as it relies on undocumented properties of the operating system, which may change at any time with updates or new versions. It will probably break also when a user uses a slideshow as desktop background, because Windows then rearranges the desktop window stack. Hack to deal with this here.
Another approach which is documented and less likely to break in future versions, with the downside of involving COM and a nightmare from C#, is via the IFolderView of shell automation, two relevant finds here and here.

Console Application with selectable text

I want the user to be able to select the text (just like in Commandprompt) where you right click on the console application's surface and a menu will show, the user can then choose same functions as in commandprompt:
Mark
Copy (Shortcut: Enter)
Paste
Select All
Scroll
Find
I have tried to Google after things like "C# Console Application select text" and other kind of things but can't seem to find a proper solution for this, since the user should be able to mark the text he/she wan't to copy or replace (with paste).
Do you have a solution for my question?

There are no managed methods to do this, but quick edit mode can be enabled through P/Invoke. Quick edit mode allows console text to be selected with the mouse and copied, and for text to be pasted with the right-moue button. (See this article for a description of quick edit mode.)
// using System.Runtime.InteropServices;
[DllImport("kernel32.dll")]
static extern bool SetConsoleMode(IntPtr hConsoleHandle, int mode);
[DllImport("kernel32.dll")]
static extern bool GetConsoleMode(IntPtr hConsoleHandle, out int mode);
[DllImport("kernel32.dll")]
static extern IntPtr GetStdHandle(int handle);
const int STD_INPUT_HANDLE = -10;
const int ENABLE_QUICK_EDIT_MODE = 0x40 | 0x80;
public static void EnableQuickEditMode()
{
int mode;
IntPtr handle = GetStdHandle(STD_INPUT_HANDLE);
GetConsoleMode(handle, out mode);
mode |= ENABLE_QUICK_EDIT_MODE;
SetConsoleMode(handle, mode);
}

maybe I didn't get you but when you execute your console application it will be hosted into a command-prompt window which allows you to copy end past text where ever you like.

You can't do context menu in console apps or in the command prompt.
Console Apps act exactly like the default cmd.exe. You need to go to the menu by clicking the icon on the top left, and the edit menu will give you the options you've listed.
You can also go to properties to turn quick edit on.

If you build the command prompt app then you'll get the select/copy/paste behavior for free. If you want to implement a right click menu (context menu) I don't think you can.
Maybe to simple but you can implement a simple switch based menu:

Simulating a keypress AND keyrelease in another application?

I need to interact with an external application running, and send specific keypresses & releases. I've tried to use the SendKeys class, but it does only half of the job, as the keypress is being sent with an immediate keyrelease to the external applications.
I need to be able to simulate a "key hold down" for the external app. I'm now trying to use the SendMessage thing, but for now it won't work at all :( and I don't even get errors.

Ok, case solved. I actually installed VC++ to try the core keybd_event() function, and after it worked I was able to use it wisely in C#.
Here's the code, and surprisingly it's very simple. You'll need to add this using to your code to be able to import dll's: using System.Runtime.InteropServices;
This code will press and hold the '1' button for 3 secs, and then will release for 1 second and repeat the process.
(the code highlight got messed up :/, copy from 'namespace ...' to the last bracket '}')
public class Program
{
[DllImport("user32.dll")]
private static extern void keybd_event(byte bVk, byte bScan,
uint dwFlags, UIntPtr dwExtraInfo);
private static void Main(string[] args)
{
while (true)
{
keybd_event((byte)0x31, (byte)0x02, 0, UIntPtr.Zero);
Thread.Sleep(3000);
keybd_event((byte)0x31, (byte)0x82, (uint)0x2, UIntPtr.Zero);
Thread.Sleep(1000);
}
}
}

have you tried using PostMessage to send WM_KEYDOWN and WM_KEYUP ?
Edit
You would use it this way (I am writing in C++, but you can easily use PInvoke and ..NET)
HWND hwnd = FindWindow(NULL,_T("Mywindow"));
PostMessage(hwnd,WM_KEYDOWN,VK_A,0);

You can use the WSH Scripting Shell to do this:
var shell = new WshShellClass();
var missing = System.Reflection.Missing.Value;
shell.SendKeys("MOO!!!", ref missing);
All you need to do is add a COM reference to "Windows Scripting Host Object", version 1.0. Everything is in the namespace IWshRuntimeLibrary.

The official API is SendInput.

Getting UI text from external app in C#

Is it possible to get UI text from an external application in C#.
In particular, is there a way to read Unicode text from a label (I assume it's a normal Windows label control) from an external Win32 app that was written by a 3rd party? The text is visible, but not selectable by mouse in the UI.
I assume there is some accessibility API (e.g. meant for screen readers) that allows this.
Edit: Currently looking into using something like the Managed Spy App but would still appreciate any other leads.

If you just care about the standard Win32 label, then WM_GETTEXT will work fine, as outlined in the other answers.
--
There is an accessibility API - UIAutomation - for standard labels, it too uses WM_GETTEXT behind the scenes. One advantage to it, however, is that it can get text from several other types of controls, including most system controls, and often UI using non-system controls - including WPF, text in IE and Firefox, and others.
// compile as:
// csc file.cs /r:UIAutomationClient.dll /r:UIAutomationTypes.dll /r:WindowsBase.dll
using System.Windows.Automation;
using System.Windows.Forms;
using System;
class Test
{
public static void Main()
{
// Get element under pointer. You can also get an AutomationElement from a
// HWND handle, or by navigating the UI tree.
System.Drawing.Point pt = Cursor.Position;
AutomationElement el = AutomationElement.FromPoint(new System.Windows.Point(pt.X, pt.Y));
// Prints its name - often the context, but would be corresponding label text for editable controls. Can also get the type of control, location, and other properties.
Console.WriteLine( el.Current.Name );
}
}

You could do it if that unicode text is actually a window with a caption by sending a WM_GETTEXT message.
[DllImport("user32.dll")]
public static extern int SendMessage (IntPtr hWnd, int msg, int Param, System.Text.StringBuilder text);
System.Text.StringBuilder text = new System.Text.StringBuilder(255) ; // or length from call with GETTEXTLENGTH
int RetVal = Win32.SendMessage( hWnd , WM_GETTEXT, text.Capacity, text);
If it is just painted on the canvas you might have some luck if you know what framework the application uses. If it uses WinForms or Borland's VCL you could use that knowledge to get to the text.

didn't see the values for wm_gettext or wm_gettextlength in that article, so just in case..
const int WM_GETTEXT = 0x0D;
const int WM_GETTEXTLENGTH = 0x0E;