C# How to translate virtual keycode to char?

Question

I am trying to map a virtual keycode to a char.

My code uses ProcessCmdKey to listen to WM_KEYDOWN which gives me access to the key pressed. For example, when I press single quote I get a key of 222 which I want to have it mapped to keychar 39 which represents... you guessed it... single quote.

My dev context is: - .net Framework 2.0 - UserControl placed in a lot of places

Do you know the answer to the question?

Answer 1

MapVirtualKey() ?

Answer 2

Assuming you are working on a windows client you might want to see this tutorial from MSDN How to: Handle Keyboard Input at the Form Level

Answer 3

Yes, I did use the MapVirtualKey method. But I was expecting more details on how to use it: what DllImport directive to use, what enum is specific for mapping to characters, etc.

I don't like these answers where you google for like 5 seconds and then just suggest a solution: the real challenge is to put all the pieces together and not have to waste your time with tons of sample-less MSDN pages or other coding forums in order to get your answer. No offense plinth, but your answer (even good) was worhtless since I had this answer even before posting my question on the forum!

So there you go, I am going to post what I was looking for - an out-of-the-box C# solution:

1. Place this directive inside your class: [DllImport("user32.dll")] static extern int MapVirtualKey(uint uCode, uint uMapType);

2. Retrieve your char like this:

 

  protected override bool ProcessCmdKey(ref Message msg, Keys keyData)      
  {
     const int WM_KEYDOWN = 0x100;

     if (msg.Msg == WM_KEYDOWN)
     {            
        // 2 is used to translate into an unshifted character value 
        int nonVirtualKey = MapVirtualKey((uint)keyData, 2);

        char mappedChar = Convert.ToChar(nonVirtualKey);
     }

     return base.ProcessCmdKey(ref msg, keyData);
  }

Thanks for caring... and enjoy!

Answer 4

Isn't that what the System.Windows.Form.KeysConverter class is for?

KeysConverter kc = new KeysConverter();
string keyChar = kc.ConvertToString(keyData);

Answer 5

KeysConverter gets the key name not the keys "text" ex: "Num2" instead of "2" MapVirtualKey will work for english but for non-english chars documentation states using MapVirtualKeyEx but that requires a locale Identifier that identifier is loaded by LoadKeyBoardLayout which requires a culture id constant but then after finding the correct id values it didn't work as i tried it so finally i dumped the whole thing