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 Edit Control Float Subclass

//##############################################################################
// Edit Control subclass callback function
//##############################################################################

LRESULT CALLBACK FloatControlSubclass(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam)
{
    int  shift   = (GetKeyState(VK_SHIFT) < 0) ? SHFT : 0;
    int  control = (GetKeyState(VK_CONTROL) < 0) ? CTRL : 0;
    int     my_id   = GetWindowLong(hwnd, GWL_ID);
    HWND    parent  = GetParent(hwnd);
    DWORD   selection;
    int     start;
    int     finish;

//    DumpMessage("'Float Subclass'", hwnd, message, wparam, lparam);

    switch(message) {
    case WM_CHAR: 
        // valid characters fall through to original window proc, invalid characters
        // return a FALSE which prevents processing.
//        if (wparam == 0x16) return FALSE; // control-v
        if (wparam == 0x03) break; // control-c
        if (wparam == 0x08) break; // control-h (backspace)
        if (wparam == 0x18) break; // control-x
        if (wparam >= '0' && wparam <= '9') break;
        if (wparam == '.') {
            char    buffer[100];
            GetWindowText(hwnd, buffer, 99);
            if (strrchr(buffer, '.') == NULL) break;
        }
        if (wparam == '-') {
            selection = Edit_GetSel(hwnd);
            start     = LOWORD(selection);
            finish    = HIWORD(selection);
            if (start == 0) break;
        }
        return FALSE;
        break;

    case WM_KEYDOWN: 
        switch(wparam + control + shift) {
        case VK_ESCAPE:
            SendMessage(parent, WM_COMMAND, MAKEWPARAM(my_id, EN_ABORT_EDIT), (LPARAM)hwnd);
            return TRUE;
        case VK_F2:
            SendMessage(parent, WM_COMMAND, MAKEWPARAM(my_id, EN_END_EDIT), (LPARAM)hwnd);
            return TRUE;
        case VK_RETURN:
            SendMessage(parent, WM_COMMAND, MAKEWPARAM(my_id, EN_COL_RIGHT), (LPARAM)hwnd);
            return TRUE;
        case CTRL + VK_HOME:
        case CTRL + VK_UP:
            SendMessage(parent, WM_COMMAND, MAKEWPARAM(my_id, EN_FIRST_ROW), (LPARAM)hwnd);
            return TRUE;
            break;
        case CTRL + VK_END:
        case CTRL + VK_DOWN:
            SendMessage(parent, WM_COMMAND, MAKEWPARAM(my_id, EN_LAST_ROW), (LPARAM)hwnd);
            return TRUE;
            break;
        case VK_UP:
            SendMessage(parent, WM_COMMAND, MAKEWPARAM(my_id, EN_ROW_UP), (LPARAM)hwnd);
            return TRUE;
            break;
        case VK_DOWN:
            SendMessage(parent, WM_COMMAND, MAKEWPARAM(my_id, EN_ROW_DOWN), (LPARAM)hwnd);
            return TRUE;
            break;
        case VK_NEXT:
            SendMessage(parent, WM_COMMAND, MAKEWPARAM(my_id, EN_PAGE_DOWN), (LPARAM)hwnd);
            return TRUE;
            break;
        case VK_PRIOR:
            SendMessage(parent, WM_COMMAND, MAKEWPARAM(my_id, EN_PAGE_UP), (LPARAM)hwnd);
            return TRUE;
            break;
        case VK_TAB:
            SendMessage(parent, WM_COMMAND, MAKEWPARAM(my_id, EN_COL_RIGHT), (LPARAM)hwnd);
            return TRUE;
            break;
        case SHFT + VK_TAB:
            SendMessage(parent, WM_COMMAND, MAKEWPARAM(my_id, EN_COL_LEFT), (LPARAM)hwnd);
            return TRUE;
            break;
        case CTRL + VK_TAB:
        case SHFT + CTRL + VK_TAB:
            // control-tab and control-shift-tab are forwarded to the parent,
            SendMessage(parent, message, wparam, lparam);
            return TRUE;
            break;
        }
    }
    // call the original window function for anything we don't care to deal with.
    return CallWindowProc((WNDPROC)GetWindowLong(hwnd, GWL_USERDATA), hwnd, message, wparam, lparam);
}

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Notebook exported on Monday, 7 July 2008, 18:56:50 PM Eastern Daylight Time