user32.dll SendMessage: Strings sent converted in uppercase characters... but case-sensitive strings

Question

I've made a program in C# that get the data info from an electronic ID card (Belgium), got no problem to do that but I need to put those informations in the registration form of a program... and that's where I got some issues...

I succeed to identify the window and the textboxes with spy++ (and select it by the FindWindow and FindWindowEx methods) but the problem is that when I'm sending a string with the SendMessage (or SendMessageW) method, my string which contains upper and lower-case characters in my software appears completely in upper-case characters in the other program... I really need to havec upper lower-case characters as well as accented characters... I tried to put the Charset in Unicode or Ansi, it doesn't change anything... Does anyone have a solution to my problem? Thanks a lot for your help!

Here is the code used:

[DllImport("user32.dll", SetLastError = true)]
private static extern IntPtr FindWindow(string lpClassName, string lpWindowName);

[DllImport("user32.dll", SetLastError = true)]
private static extern IntPtr FindWindowEx(IntPtr hwndParent, IntPtr hwndChildAfter, string className, string lpszWindow);

[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = false)]
private static extern int SendMessage(IntPtr hWnd, uint msg, IntPtr wParam, string lParam);

[DllImport("user32.dll", EntryPoint = "SendMessageW", CharSet = CharSet.Unicode)]
static extern IntPtr SendMessageUnicode(IntPtr hWnd, UInt32 Msg, IntPtr wParam, [MarshalAs(UnmanagedType.LPWStr)] string lParam);

private const int WM_SETTEXT = 12;

...

IntPtr x = new IntPtr();
IntPtr parent = FindWindow(null, "Formulaire inscription lecteur");
IntPtr child = FindWindowEx(parent, x, "Edit", null);
int q = SendMessage(child, WM_SETTEXT, IntPtr.Zero, "TesT");
// same thing with this://SendMessageUnicode(child, WM_SETTEXT, IntPtr.Zero, "TeSt");

Here is what I get on the registration form:

Edit:

Thanks for your answers... I used xMRi's method and it works perfectly...

In case, here is the code used to do that (cause there is a lot of not working codes out there):

        [DllImport("user32.dll")]
        static extern int SetWindowLong(IntPtr hWnd, int nIndex, UInt32 dwNewLong);


        [DllImport("user32.dll")]
        public static extern IntPtr GetWindowLong(IntPtr hWnd, GetWindowLongParam nCmd);

        private const int WM_SETTEXT = 12;
        private const int GWL_STYLE = (-16);
        private const int ES_UPPERCASE = 0x0008;
        private const int ES_READONLY = 0x0800;
        private const int DTM_SETSYSTEMTIME = 0x1002;
        public enum GetWindowLongParam
    {
        GWL_WNDPROC   =      (-4),
        GWL_HINSTANCE =      (-6),
        GWL_HWNDPARENT=      (-8),
        GWL_STYLE     =      (-16),
        GWL_EXSTYLE   =      (-20),
        GWL_USERDATA  =      (-21),
        GWL_ID        =      (-12),
    }


                    IntPtr x = new IntPtr();
                    IntPtr parent = FindWindow(null, "Formulaire inscription lecteur");
                    IntPtr child = FindWindowEx(parent, x, "Edit", null);
                    //defining style: 1. Get the styles, and then delete uppercase and readonly
                    lExStyle = (long)GetWindowLong(child, GetWindowLongParam.GWL_STYLE);
                    lExStyle &= ~(ES_UPPERCASE);
                    lExStyle &= ~(ES_READONLY);
                    //set the new styles
                    SetWindowLong(child, GWL_STYLE, (uint)lExStyle);
                    //then send the message
                    SendMessage(child, WM_SETTEXT, IntPtr.Zero, string);

The only problem to put data in the other program is on an "Edit" but linked to a sysmonthcal32 ... I tried to send it in different forms, overridden the readonly style, ... nothing seems to work...

All the others "edit" are filled with the strings sent by my software...

http://i.stack.imgur.com/dRaS8.png

Any ideas?

Thanks a lot!

Answer 1

Use Spy++. Look at the target window. I am sure that the target edit control has the style ES_UPPERCASE! So this tells you why the characters are converted.

You may do a dirty hack in using SetWindowLong(GWL_STYLE) and remove this style.

Answer 2

The other program is converting your text to upper case. There's nothing you can do from your end. You'll need to get help from the developer of the other program.