How does TextBox get text from key input? (Basic TextBox Method)

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So I'm wondering how it is done, I asked on msdn and viewed the TextBox code and got completely lost so I decided to kindly ask here :)
I simply want to write a method that looks like that

char GetChar(int keycode, bool shiftState, object something/*Arabic(101), Arabic(102), Albanian, English(US), English(UK)...etc CultureInfo maybe*/)
{
    char output = '\0';
    bool capsLock = (((ushort)GetKeyState(0x14)) & 0xffff) != 0;
    //Some code....
    return output;
}

Posted 9-Jul-11 8:21am

Hesham_h4

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Sergey Alexandrovich Kryukov 10-Jul-11 3:24am

Tag it! WPF, Forms, what?!
--SA

3 solutions

Solution 2

You should do it handling the event KeyPress. The event arguments of this event will give you the key character pressed; you can compare it with the Unicode code point ranges you expect for input and issue the warning. Alternatively (or better additionally), you can filter out unwanted characters as this event can be cancelled; use the value of property Cancel to true (this is the property if the event arguments parameter).

—SA

Posted 9-Jul-11 21:30pm

Sergey Alexandrovich Kryukov

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Espen Harlinn 10-Jul-11 7:50am

My 5 - If he is going to do it himself, this is where he needs to start - but getting it right might be a bit of a challenge.

Sergey Alexandrovich Kryukov 10-Jul-11 13:33pm

Thank you, Espen.
Challenge or not, but this is what should be done, no less.
--SA

Espen Harlinn 10-Jul-11 13:50pm

He could just change the input language for the UI thread of his application - that would be quite easy :)

Sergey Alexandrovich Kryukov 12-Jul-11 16:16pm

Well, the question is reasonable. (By the way, I don't know how to change input language programmatically, this is not UI culture; do you know? WMI?) So, the question is reasonable: instead of forcing the user into different input it would simply warn and notify which language is expected.
--SA

Espen Harlinn 12-Jul-11 16:50pm

ehrm ... :blush: ... try looking at my "solution" ...

Hesham_h4 17-Jul-11 23:43pm

The thing we are trying to achieve here is much more different than what I was trying to do. I don't know for sure that the user is going to use a specific language to warn him about a wrong one, I could have used a character set for that. I'm intending to search the word list of every language upon user input to tell what language the user might be typing without it necessarily selected.
That requires:
1. Keyboard layout.
2. Keycode + Shift, Alt and Ctrl state.
3. Making an assumption out of this input for every known language.
4. Comparing these assumptions to word lists and detecting at which language this input may mean something. Google has super systems so I'm NOT expecting this to be done in a flash on an ordinary or even gaming computer. It's just interesting to do it.
Check the picture again please, I was typing English while the keyboard is switched to Arabic and it was detected to be English and automatically translated, same thing happens if you write Arabic with the keyboard set to Spanish, if you know what I mean!

Hesham_h4 17-Jul-11 23:53pm

As a second thought this can be simplified if we consider installed languages only but as is it can help people use their language without installation, just type your language in any installed language and we will understand your input, that seems great.

Solution 3

From the previous discussion I think this is what you need:
InputLanguage.CurrentInputLanguage[^] - this property gets or sets the input language for the current thread.

Use InputLanguageCollection[^] as the source of available input languages.

Best regards
Espen Harlinn

Posted 10-Jul-11 1:47am

Espen Harlinn

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Hesham_h4 17-Jul-11 23:50pm

Knowing the input language might help finding out that the input isn't recognized as words in the selected input language and so trigger the whole process. I think you found the trigger, but we still don't have a gun :)

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Heath Stewart · Accepted Answer · 2011-07-09T08:35:00

Solution 1

A TextBox (assuming you mean System.Windows.Forms.TextBox - please be specific if not) is actually a wrapper around the Win32 Edit common control, so text is actually posted to a window handle (HWND) and native code in Windows handles processing.

But a TextBox can handle input by overriding OnKeyDown (or handling the KeyDown event if you don't want to subclass).

However, I'm not clear from your question what it is you're trying to do. If we could understand what you're trying to do (and not just a question on a preconceived how) we could better propose a solution.

Posted 9-Jul-11 8:35am

Heath Stewart

Comments

Hesham_h4 9-Jul-11 19:14pm

Thanks for replying, what I mainly try to do here is to get text in a specified language from text typed in another language.
What I came up with is to convert that text (Given the language/keyboard layout) to a keycode array (Including shift state) then do what I'm trying to do here.
For example if we have the text "فاهس هس ُىلمهسا" that's in Arabic(101), I want to predict the text written in English (Assuming that the user forgot to switch language) which is "this is English".

Of course if there's another way to do that I'd love to know.

P.S: Google is already using such a method in the search bar.
http://imageshack.us/photo/my-images/89/capturece.jpg/[^]

Sergey Alexandrovich Kryukov 10-Jul-11 3:32am

Sure. In my solution I answered exactly this question (and not your initial question above).
--SA

Sergey Alexandrovich Kryukov 10-Jul-11 3:32am

Considering you did not read the follow-up question by OP, this is a good answer, my 5. As to this question -- I've answered; please see my solution.
--SA

Espen Harlinn 10-Jul-11 7:37am

Good reply, my 5

Hesham_h4 18-Jul-11 0:49am

This is actually the answer to the Title questions though not answering the Main one but I decided to ask it separately.