How to Read a keyboard input on an application?

[bmerlover]

I currently have a gui app I programmed with visual c++ .net version. Is there any way I can read any character from the keyboard as soon as any key is pressed while the application is running? My intention is that as soon as a specific key is pressed, the app is suppose to take the appropriate action. All the functions work, so all I would have to do is call the function as soon as a key is pressed from the keyboard? I am not asking the user for an input, it's just if the user does hit a keyboard key it will take the key as an input and call the function.

Thanks in advance.

[Atran]

I currently have a gui app I programmed with visual c++ .net version. Is there any way I can read any character from the keyboard as soon as any key is pressed while the application is running? My intention is that as soon as a specific key is pressed, the app is suppose to take the appropriate action. All the functions work, so all I would have to do is call the function as soon as a key is pressed from the keyboard? I am not asking the user for an input, it's just if the user does hit a keyboard key it will take the key as an input and call the function.

Thanks in advance.

Hello:
Try this code:

private: System::Void Form1_Load(System::Object^  sender, System::EventArgs^  e) {
        //Start from Here:
        Control ^ Ctrl = gcnew Control();
        Ctrl->KeyDown += gcnew System::Windows::Forms::KeyEventHandler(this, &Form1::Ctrl_KeyDown);
        Controls->Add(Ctrl);
    }
private: System::Void Ctrl_KeyDown(Object^ sender, System::Windows::Forms::KeyEventArgs^  e) {
            if(e->KeyData == Keys::Space)
            {
                 ShowMessageBox("You pressed Space key.");
            }
        if(e->KeyCode == Keys::Enter)
        {
            ShowMessageBox("You pressed Enter key.");
        }
    }
 
private: System::Void ShowMessageBox(System::String^ msg) {
        MessageBox::Show(msg, "Key Pressed");
    }
};
 

Hope I helped you.

[bmerlover]

Thanks for the response, I'm working with an older version of .net, I believe its 2003. I modified the code so that I won't get any errors, nothing major, just had to change ^ to * and gcnew to new. I'm going to continue to work on it to get it to work. Thanks again.

[Plater]

You can register a global hook for your program, it pretty much will allow you to have a function like:

void globalkeypressed(object ContainsKeyData)
{
   if (ContainsKeyData.Key==Keys.A)
   {
      //do something
   }
}
 

I have only been finding ways to stick global hooks into C#/VB.NET as they're much more native to c++. But you should be able to use it.

http://msdn2.microsoft.com/en-us/library/ms644959.aspx

The important function to get at is: (this is C#, but you can see where it's comming from)

//Use this function to install a thread-specific hook.
[DllImport("user32.dll",CharSet=CharSet.Auto,
 CallingConvention=CallingConvention.StdCall)]
public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, 
IntPtr hInstance, int threadId);
 

(http://support.microsoft.com/kb/318804 )

[bmerlover]

Thanks Atran and Plater for the help. You both gave me good ideas. I just found this site which was very helpful. I modified it a bit so that it won't give me messages instead it just calls the function I want. Works Great. Haven't found any bugs yet, although I still have a lot more testing to do.

http://support.microsoft.com/kb/839201

[Plater]

Hehe, oh yeah, you said you only wanted to capture when your program was active, my bad.

Thanks Atran and Plater for the help. You both gave me good ideas. I just found this site which was very helpful. I modified it a bit so that it won't give me messages instead it just calls the function I want. Works Great. Haven't found any bugs yet, although I still have a lot more testing to do.

http://support.microsoft.com/kb/839201