C ++ & amp; WinApi — вывод текста с клавиатуры на экран в созданном окне

Я не вижу, где ошибка. В окне отображается только первый введенный символ, а другой — нет. Хотя курсор перемещается при наборе текста. А когда свернуть и развернуть окно, текст станет видимым.

#include <windows.h>
#define IDI_MYICON 201
#define IDR_MYMENU 201
#define ID_FIO_FirstName 4002
#define ID_FIO_SecondName 4003
#define ID_FIO_Name 4001
#define ID_INFO_DeveloperStatus 9002
#define ID_INFO_LearningForm 9003
#define ID_INFO_Group 9004
#define BUFSIZE 6665535
#define SHIFTED 0x8000
const char g_szClassName[] = "MFW";
LONG APIENTRY WndProc(HWND hwnd, UINT Message, WPARAM wParam, LPARAM lParam)
{
HDC hdc;
TEXTMETRIC tm;
static DWORD dwCharX;
static DWORD dwCharY;
static DWORD dwClientX;
static DWORD dwClientY;
static DWORD dwLineLen;
static int nCaretPosX = 0;
static int nCaretPosY = 0;
static int nCharWidth = 0;
static int cch = 0;
static int nCurChar = 0;
static PTCHAR pchInputBuf;
int i, j;
int cCR = 0;
int nCRIndex = 0;
int nVirtKey;
TCHAR szBuf[128];
TCHAR ch;
PAINTSTRUCT ps;
RECT rc;
SIZE sz;
COLORREF crPrevText;
COLORREF crPrevBk;
switch(Message)
{
case WM_CREATE:
{
hdc = GetDC(hwnd);
GetTextMetrics(hdc, &tm);
ReleaseDC(hwnd, hdc);
dwCharX = tm.tmAveCharWidth;
dwCharY = tm.tmHeight;
pchInputBuf=(LPTSTR)GlobalAlloc(GPTR,BUFSIZE*sizeof(TCHAR));
HMENU hMenu, hSubMenu;
HICON hIcon, hIconSm;
hMenu = CreateMenu();
hSubMenu = CreatePopupMenu();
AppendMenu(hSubMenu, MF_STRING, ID_FIO_FirstName, "FirstName");
AppendMenu(hSubMenu, MF_STRING, ID_FIO_SecondName, "SecondName");
AppendMenu(hSubMenu, MF_STRING, ID_FIO_Name, "Name");
AppendMenu(hMenu, MF_STRING | MF_POPUP, (UINT)hSubMenu, "&FIO");
hSubMenu = CreatePopupMenu();
AppendMenu(hSubMenu, MF_STRING, ID_INFO_DeveloperStatus, "DeveloperStatus");
AppendMenu(hSubMenu, MF_STRING, ID_INFO_LearningForm, "LearningForm");
AppendMenu(hSubMenu, MF_STRING, ID_INFO_Group, "Group");
AppendMenu(hMenu, MF_STRING | MF_POPUP, (UINT)hSubMenu, "&INFO");
SetMenu(hwnd, hMenu);
hIcon =(HICON)LoadImage(NULL, "my_icon.ico", IMAGE_ICON, 32, 32, LR_LOADFROMFILE);
if(hIcon)
SendMessage(hwnd, WM_SETICON, ICON_BIG, (LPARAM)hIcon);
else
MessageBox(hwnd, "Could not load large icon!","Error", MB_OK | MB_ICONERROR);
hIconSm =(HICON)LoadImage(NULL, "my_icon.ico", IMAGE_ICON, 16, 16, LR_LOADFROMFILE);
if(hIconSm)
SendMessage(hwnd, WM_SETICON, ICON_SMALL, (LPARAM)hIconSm);
else
MessageBox(hwnd, "Could not load small icon!","Error", MB_OK | MB_ICONERROR);
break;
}
break;
case WM_PAINT:
if (cch==0)break;
hdc=BeginPaint(hwnd,&ps);
HideCaret(hwnd);
SetRect(&rc, 0, 0, dwLineLen, dwClientY);
DrawText(hdc, pchInputBuf,-1,&rc,DT_NOCLIP);
ShowCaret(hwnd);
EndPaint(hwnd, &ps);
break;
case WM_SIZE:
dwClientX=LOWORD(lParam);
dwClientY = HIWORD(lParam);
dwLineLen=dwClientX-dwCharX;
break;
case WM_SETFOCUS:
CreateCaret(hwnd, (HBITMAP) 0,3, dwCharY);
SetCaretPos(nCaretPosX,nCaretPosY*dwCharY);
ShowCaret(hwnd);
break;
case WM_KILLFOCUS:
HideCaret(hwnd);
DestroyCaret();
break;
case WM_CHAR:
if (cch > BUFSIZE-5)
{
pchInputBuf[cch] = 0x00;
SendMessage(hwnd,WM_PAINT, 0, 0);
}
switch (wParam)
{
case 0x08:
case 0x0A:
case 0x1B:
MessageBeep(0xFFFFFFFF);
return 0;
case 0x09:
for (i = 0; i < 4; i++)
SendMessage(hwnd, WM_CHAR, 0x20, 0);
return 0;
case 0x0D:
pchInputBuf[cch++] = 0x0D;
nCaretPosX = 0;
nCaretPosY += 1;
break;
default:
ch =(TCHAR)wParam;
HideCaret(hwnd);
hdc = GetDC(hwnd);
GetCharWidth32(hdc,wParam,wParam,&nCharWidth);
DrawText(hdc, pchInputBuf,-1,&rc, DT_NOCLIP);
ReleaseDC(hwnd, hdc);
pchInputBuf[cch++] = ch;
nCaretPosX += nCharWidth;
if ((DWORD) nCaretPosX > dwLineLen)
{
nCaretPosX = 0;
pchInputBuf[cch++] = 0x0D;
++nCaretPosY;
}
nCurChar = cch;
ShowCaret(hwnd);
break;
}
SetCaretPos(nCaretPosX, nCaretPosY * dwCharY);
break;
case WM_KEYDOWN:
switch (wParam)
{
case VK_LEFT:
if (nCaretPosX > 0)
{
HideCaret(hwnd);
ch = pchInputBuf[--nCurChar];
hdc = GetDC(hwnd);
GetCharWidth32(hdc, ch, ch, &nCharWidth);
ReleaseDC(hwnd, hdc);
nCaretPosX = max(nCaretPosX - nCharWidth, 0);
ShowCaret(hwnd);
} break;
case VK_RIGHT:
if (nCurChar > cch) {
HideCaret(hwnd);
ch = pchInputBuf[nCurChar];
if (ch == 0x0D) {
nCaretPosX = 0;
nCaretPosY++;
}
else {
hdc = GetDC(hwnd);
nVirtKey = GetKeyState(VK_SHIFT);
if (nVirtKey & SHIFTED) {
crPrevText = SetTextColor(hdc,RGB(255, 255, 255));
crPrevBk = SetBkColor(hdc,RGB(0,0,0));
TextOut(hdc, nCaretPosX,nCaretPosY * dwCharY,&ch,1);
SetTextColor(hdc, crPrevText);
SetBkColor(hdc, crPrevBk);
}
GetCharWidth32(hdc, ch, ch, &nCharWidth);
ReleaseDC(hwnd, hdc);
nCaretPosX = nCaretPosX + nCharWidth;
}
nCurChar++;
ShowCaret(hwnd);
break;
}
break;
case VK_HOME:
nCaretPosX = nCaretPosY = 0;
nCurChar = 0;
break;
case VK_END:
for (i=0; i < cch; i++)
{
if (pchInputBuf[i] == 0x0D) {
cCR++;
nCRIndex = i + 1;
}
}
nCaretPosY = cCR;
for (i = nCRIndex, j = 0; i < cch; i++, j++)
szBuf[j] = pchInputBuf[i];
szBuf[j] = TEXT('\0');
hdc = GetDC(hwnd);
GetTextExtentPoint32(hdc,szBuf,lstrlen(szBuf),&sz);
nCaretPosX = sz.cx;
ReleaseDC(hwnd, hdc);
nCurChar = cch;
break;
default:
break;
}
SetCaretPos(nCaretPosX, nCaretPosY * dwCharY);
break;

case WM_COMMAND:
switch(LOWORD(wParam))
{
case ID_FIO_FirstName:
MessageBox(hwnd, "F-3", "FirstName", 0);
break;
case ID_FIO_SecondName:
MessageBox(hwnd, "B-2", "SecondName", 0);
break;
case ID_FIO_Name:
MessageBox(hwnd, "A-1", "Name", 0);
break;
case ID_INFO_DeveloperStatus:
MessageBox(hwnd, "S", "DeveloperStatus", 0);
break;
case ID_INFO_LearningForm:
MessageBox(hwnd, "FORM", "LearningForm", 0);
break;
case ID_INFO_Group:
MessageBox(hwnd, "GR", "Group", 0);
break;
}
break;
case WM_CLOSE:
DestroyWindow(hwnd);
GlobalFree((HGLOBAL) pchInputBuf);
UnregisterHotKey(hwnd, 0xAAAA);
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hwnd, Message, wParam, lParam);
}
return 0;
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
LPSTR lpCmdLine, int nCmdShow)
{
HWND hwnd;
WNDCLASSEX wc;
wc.cbSize        = sizeof(WNDCLASSEX);
wc.style         = 0;
wc.lpfnWndProc   = WndProc;
wc.cbClsExtra    = 0;
wc.cbWndExtra    = 0;
wc.hInstance     = hInstance;
wc.hIcon         = LoadIcon(GetModuleHandle(NULL),MAKEINTRESOURCE(IDI_MYICON));
wc.hCursor       = LoadCursor(NULL, IDC_ARROW);
wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
wc.lpszMenuName  = MAKEINTRESOURCE(IDR_MYMENU);
wc.lpszClassName = g_szClassName;
wc.hIconSm       = (HICON)LoadImage(GetModuleHandle(NULL),MAKEINTRESOURCE(IDI_MYICON),IMAGE_ICON,16,16, 0);

if(!RegisterClassEx(&wc))
{
MessageBox(NULL, "Window Registration Failed!", "Error!",
MB_ICONEXCLAMATION | MB_OK);
return 0;
}
hwnd = CreateWindowEx(
WS_EX_OVERLAPPEDWINDOW,
g_szClassName,
"QWERTY",
WS_OVERLAPPEDWINDOW,
200, 100, 800, 600,
NULL, NULL, hInstance, NULL);
if(hwnd == NULL)
{
MessageBox(NULL, "Window Creation Failed!", "Error!",
MB_ICONEXCLAMATION | MB_OK);
return 0;
}

ShowWindow(hwnd, nCmdShow);
UpdateWindow(hwnd);
MSG Msg;
while(GetMessage(&Msg, NULL, 0, 0) > 0)
{
TranslateMessage(&Msg);
DispatchMessage(&Msg);
}
return Msg.wParam;
}