Using EDITSTREAM CALLBACK

Question

Hallo everyone! I've been having trouble using the EDIT STREAM CALLBACK.When I try to run my application, it fails with unhand-led exception access violation.Here my code.Any help will be highly appreciated.
case ID_BUTTONA:
            DWORD_PTR dwCookie;
    dwCookie = 0;
    DWORD   dwError;
    dwError = 0;
    EDITSTREAMCALLBACK EditStreamCallback;
    EditStreamCallback = NULL ;
    EDITSTREAM es;  
    hFile = (HANDLE)dwCookie;   
es.dwCookie    = (DWORD_PTR)hFile;
es.dwError =    dwError;
es.pfnCallback = EditStreamCallback;
    LPBYTE pbBuff;
    pbBuff = NULL;
    LONG cb;
    PLONG pcb;
    pcb = 0;
    DWORD   write;
     WriteFile(hFile, &pbBuff, write, (DWORD *)&pcb, NULL);//
dwpfn=GetLastError();
      swprintf_s(dwj,100,L"%d",dwpfn);
                        MessageBox(hWnd, dwj
                                   L"Problem with write file",
MB_OK);
EditStreamCallback( (DWORD_PTR)hFile ,pbBuff,cb,pcb);
SendMessage(richedit, EM_STREAMOUT, SF_RTF, (LPARAM)&es);
    hFile = CreateFile(L"Again.rtf",GENERIC_WRITE,
                              FILE_SHARE_WRITE, 0, CREATE_NEW,
                              FILE_ATTRIBUTE_NORMAL, NULL);
    if (hFile=INVALID_HANDLE_VALUE)
    dw2=GetLastError();
      swprintf_s(dw3,100,L"%d",dw2);
                        MessageBox(hWnd, dw3
                                   L"INVALID_HANDLE_VALUE",
                                   MB_OK);
            case IDM_OPEN:
       hr = CoInitializeEx(NULL, COINIT_APARTMENTTHREADED |
        COINIT_DISABLE_OLE1DDE);
    if (SUCCEEDED(hr))
          MessageBox(hWnd1, L"com is registered"
                                   L"Error 2",
                                   MB_OK);
        IFileOpenDialog *pFileOpen;
        hr = CoCreateInstance(CLSID_FileOpenDialog, NULL, CLSCTX_ALL,
                IID_IFileOpenDialog, reinterpret_cast<void**>(&pFileOpen));
        if (SUCCEEDED(hr))
            hr = pFileOpen->Show(NULL);
            if (SUCCEEDED(hr))
                IShellItem *pItem;
                hr = pFileOpen->GetResult(&pItem);
                if (SUCCEEDED(hr))
                    PWSTR pszFilePath;
                    hr = pItem->GetDisplayName(SIGDN_FILESYSPATH, &pszFilePath);
                    if (SUCCEEDED(hr))
                        MessageBox(NULL, pszFilePath, L"File Path", MB_OK);
    HANDLE hFile1 = CreateFile(pszFilePath, GENERIC_READ,
                              0, NULL, OPEN_EXISTING,
                              FILE_FLAG_SEQUENTIAL_SCAN, NULL);
if (hFile1 = INVALID_HANDLE_VALUE)
    {dwe=GetLastError();
      swprintf_s(dwe5,100,L"%d",dwe);
                        MessageBox(hWnd1, dwe5
                                   L"Error INVALID_HANDLE_VALUE",
                                   MB_OK);
  ReadFile(hFile1, &pbBuff1, sizeof(cb1), (DWORD *)&pcb1, NULL);
pcb1 = 0;
cb1 = 100;
dwCookie    = (DWORD_PTR)hFile1;
pfnCallback1 = NULL ;
dwError= 0;
pfnCallback1(dwCookie,pbBuff1,cb1,pcb1);
EDITSTREAM es1 = { 0 };
es1.pfnCallback = pfnCallback1;
es1.dwCookie    = (DWORD_PTR)hFile1;
es1.dwError =    dwError;
if (SendMessage(richedit1, EM_STREAMIN, SF_RTF, (LPARAM)&es1) && es1.dwError == 0)
CoTaskMemFree(pszFilePath);
        CloseHandle(hFile1);
                    pItem->Release();
            pFileOpen->Release();
        CoUninitialize();
// Basics.cpp : Defines the entry point for the application.
#include "stdafx.h"
#include "Basics.h"
#include "windows.h"
#include "Winuser.h"
#include <stdio.h>
#include "Richedit.h"
#include <shobjidl.h>
#define MAX_LOADSTRING 100
#define ID_BUTTONA      200
#define  ID_BUTTONB 201
// Global Variables:
HINSTANCE hInst;                                // current instance
TCHAR szTitle[MAX_LOADSTRING];                    // The title bar text
TCHAR szWindowClass[MAX_LOADSTRING];            // the main window class name
// Forward declarations of functions included in this code module:
ATOM                MyRegisterClass(HINSTANCE hInstance);
BOOL                InitInstance(HINSTANCE, int);
LRESULT CALLBACK    WndProc(HWND, UINT, WPARAM, LPARAM);
LRESULT CALLBACK    WndProc1(HWND, UINT, WPARAM, LPARAM);
INT_PTR CALLBACK    About(HWND, UINT, WPARAM, LPARAM);
int APIENTRY _tWinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPTSTR    lpCmdLine,
                     int       nCmdShow)
    UNREFERENCED_PARAMETER(hPrevInstance);
    UNREFERENCED_PARAMETER(lpCmdLine);
     // TODO: Place code here.
    MSG msg;
    HACCEL hAccelTable;
    // Initialize global strings
    LoadString(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING);
    LoadString(hInstance, IDC_BASICS, szWindowClass, MAX_LOADSTRING);
    MyRegisterClass(hInstance);
    // Perform application initialization:
    if (!InitInstance (hInstance, nCmdShow))
        return FALSE;
    hAccelTable = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDC_BASICS));
    // Main message loop:
    while (GetMessage(&msg, NULL, 0, 0))
        if (!TranslateAccelerator(msg.hwnd, hAccelTable, &msg))
            TranslateMessage(&msg);
            DispatchMessage(&msg);
    return (int) msg.wParam;
//  FUNCTION: MyRegisterClass()
//  PURPOSE: Registers the window class.
//  COMMENTS:
//    This function and its usage are only necessary if you want this code
//    to be compatible with Win32 systems prior to the 'RegisterClassEx'
//    function that was added to Windows 95. It is important to call this function
//    so that the application will get 'well formed' small icons associated
//    with it.
ATOM MyRegisterClass(HINSTANCE hInstance)
    WNDCLASSEX wcex;
    wcex.cbSize = sizeof(WNDCLASSEX);
    wcex.style            = CS_HREDRAW | CS_VREDRAW;
    wcex.lpfnWndProc    = WndProc;
    wcex.cbClsExtra        = 0;
    wcex.cbWndExtra        = 0;
    wcex.hInstance        = hInstance;
    wcex.hIcon            = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_BASICS));
    wcex.hCursor        = LoadCursor(NULL, IDC_ARROW);
    wcex.hbrBackground    = (HBRUSH)(COLOR_WINDOW+1);
    wcex.lpszMenuName    = MAKEINTRESOURCE(IDC_BASICS);
    wcex.lpszClassName    = szWindowClass;
    wcex.hIconSm        = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_SMALL));
     WNDCLASSEX wcex1;    
    wcex1.cbSize = sizeof(WNDCLASSEX);
    wcex1.style            = CS_HREDRAW | CS_VREDRAW;
    wcex1.lpfnWndProc    = WndProc1;
    wcex1.cbClsExtra        = 0;
    wcex1.cbWndExtra        = 0;
    wcex1.hInstance        = hInstance;
    wcex1.hIcon            = NULL;
    wcex1.hCursor        = LoadCursor(NULL, IDC_ARROW);
    wcex1.hbrBackground    = (HBRUSH)(COLOR_WINDOW+1);
    wcex1.lpszMenuName    = MAKEINTRESOURCE ( IDC_BASICS);
    wcex1.lpszClassName    = L"NEW CLASS";
    wcex1.hIconSm        = NULL;
    RegisterClassEx(&wcex1);
    return RegisterClassEx(&wcex);
//   FUNCTION: InitInstance(HINSTANCE, int)
//   PURPOSE: Saves instance handle and creates main window
//   COMMENTS:
//        In this function, we save the instance handle in a global variable and
//        create and display the main program window.
BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
   HWND hWnd;
   hInst = hInstance; // Store instance handle in our global variable
   hWnd = CreateWindow(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
      CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL);
   if (!hWnd)
      return FALSE;
   ShowWindow(hWnd, nCmdShow);
   UpdateWindow(hWnd);
   return TRUE;
//  FUNCTION: WndProc(HWND, UINT, WPARAM, LPARAM)
//  PURPOSE:  Processes messages for the main window.
//  WM_COMMAND    - process the application menu
//  WM_PAINT    - Paint the main window
//  WM_DESTROY    - post a quit message and return
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
    int wmId, wmEvent;
    PAINTSTRUCT ps;
    HDC hdc;
    HWND hwndButton;
    HWND hwndButtona;
    HWND richedit;
    HANDLE hFile;
    HINSTANCE hInstance;
    switch (message)
        DWORD dw;
    WCHAR dw1[100];
    DWORD dw2;
    WCHAR dw3[100];
    DWORD dwpfn;
    WCHAR dwj[100];
   case WM_CREATE:
             hwndButton = CreateWindow(
    L"BUTTON",  // Predefined class; Unicode assumed
    L"OK",      // Button text
    WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON,  // Styles
    200,         // x position
    160,         // y position
    150,        // Button width
    100,        // Button height
    hWnd,     // Parent window
    NULL,       // No menu.
    (HINSTANCE)GetWindowLong(hWnd, GWL_HINSTANCE),
    NULL);      // Pointer not needed.
             LoadLibrary(L"Msftedit.dll");
    richedit = CreateWindowEx(
    WS_EX_ACCEPTFILES | WS_EX_CLIENTEDGE,
    MSFTEDIT_CLASS,
    L"MSFTEDIT_CLASS",
    WS_CHILD | WS_VISIBLE |ES_AUTOHSCROLL | ES_LEFT| ES_SELECTIONBAR| ES_SUNKEN | ES_SAVESEL | ES_AUTOVSCROLL ,
    0,
    0,                  // starting x- and y-coordinates
    0,        // width of client area
    0,  
    hWnd,
    NULL,    
    (HINSTANCE)GetWindowLong(hWnd, GWL_HINSTANCE),
     NULL);
if (!richedit)
    dw=GetLastError();
      swprintf_s(dw1,100,L"%d",dw);
                        MessageBox(hWnd, dw1
                                   L"Error richedit",
                                   MB_OK);
 SendMessage(richedit, WM_CONTEXTMENU, 0, 0);
  SetWindowPos(
    richedit,
    NULL,
    180,
    265,
    190,
    25,
    NULL);
           hwndButtona = CreateWindow(
    L"BUTTON",  // Predefined class; Unicode assumed
    L"OK",      // Button text
    WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON,  // Styles
    380,         // x position
    265,         // y position
    25,        // Button width
    25,        // Button height
    hWnd,     // Parent window
    (HMENU) ID_BUTTONA,       // No menu.
    (HINSTANCE)GetWindowLong(hWnd, GWL_HINSTANCE),
    NULL);      // Pointer not needed.
        break;
    case WM_COMMAND:
        wmId    = LOWORD(wParam);
        wmEvent = HIWORD(wParam);
        // Parse the menu selections:
        switch (wmId)
        case IDM_ABOUT:
            DialogBox(hInst, MAKEINTRESOURCE(IDD_ABOUTBOX), hWnd, About);
            break;
            case ID_BUTTONA:
            DWORD_PTR dwCookie;
    dwCookie = 0;
    DWORD   dwError;
    dwError = 0;
    EDITSTREAMCALLBACK EditStreamCallback;
    EditStreamCallback = NULL ;
    EDITSTREAM es;  
    hFile = (HANDLE)dwCookie;   
es.dwCookie    = (DWORD_PTR)hFile;
es.dwError =    dwError;
es.pfnCallback = EditStreamCallback;
    LPBYTE pbBuff;
    pbBuff = NULL;
    LONG cb;
    PLONG pcb;
    pcb = 0;
    DWORD   write;
     WriteFile(hFile, &pbBuff, write, (DWORD *)&pcb, NULL);//
dwpfn=GetLastError();
      swprintf_s(dwj,100,L"%d",dwpfn);
                        MessageBox(hWnd, dwj
                                   L"Problem with write file",
MB_OK);
EditStreamCallback( (DWORD_PTR)hFile ,pbBuff,cb,pcb);
SendMessage(richedit, EM_STREAMOUT, SF_RTF, (LPARAM)&es);
    hFile = CreateFile(L"Again.rtf",GENERIC_WRITE,
                              FILE_SHARE_WRITE, 0, CREATE_NEW,
                              FILE_ATTRIBUTE_NORMAL, NULL);
    if (hFile=INVALID_HANDLE_VALUE)
    dw2=GetLastError();
      swprintf_s(dw3,100,L"%d",dw2);
                        MessageBox(hWnd, dw3
                                   L"INVALID_HANDLE_VALUE",
                                   MB_OK);                  
   HWND hWnd1;
   hWnd1 = CreateWindow(L"NEW CLASS", L"Window 2", NULL,
      0, 0, 980, 700, NULL, NULL, hInstance, NULL);
   dw2=GetLastError();
      swprintf_s(dw3,100,L"%d",dw2);
                        MessageBox(hWnd, dw3
                                   L"INVALID_HANDLE_VALUE",
                                   MB_OK);
   if (!hWnd1)
      MessageBox(hWnd,  L"CreateWindow failed"
                                   L"Error CreateWindow",
                                   MB_OK);
   ShowWindow(hWnd1, SW_SHOW);
   UpdateWindow(hWnd1);
   ShowWindow(hWnd, SW_HIDE);
   return TRUE;
        case IDM_EXIT:
            DestroyWindow(hWnd);
            break;
        default:
            return DefWindowProc(hWnd, message, wParam, lParam);
        break;
    case WM_PAINT:
        hdc = BeginPaint(hWnd, &ps);
        // TODO: Add any drawing code here...
        EndPaint(hWnd, &ps);
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    default:
        return DefWindowProc(hWnd, message, wParam, lParam);
    return 0;
LRESULT CALLBACK WndProc1(HWND hWnd1, UINT message, WPARAM wParam, LPARAM lParam)
    int wmId, wmEvent;
    PAINTSTRUCT ps;
    HDC hdc;
    HWND richedit1;
    DWORD dwe;
    WCHAR dwe5[100];
    DWORD dw4;
    WCHAR dw5[100];
    LPBYTE pbBuff1;
    LONG cb1;
    PLONG pcb1;
    DWORD_PTR dwCookie;
    DWORD   dwError;
    EDITSTREAMCALLBACK pfnCallback1;
    HRESULT hr;
    HWND hwndButtonb;
    switch (message)
    case WM_CREATE:
        LoadLibrary(L"Msftedit.dll");
    richedit1 = CreateWindowEx(
        WS_EX_ACCEPTFILES | WS_EX_CLIENTEDGE, MSFTEDIT_CLASS,
    L"MSFTEDIT_CLASS",
    WS_CHILD | WS_VISIBLE |ES_AUTOHSCROLL | ES_LEFT| ES_SELECTIONBAR| ES_SUNKEN | ES_SAVESEL | ES_MULTILINE | ES_AUTOVSCROLL ,
    0,
    0,                  // starting x- and y-coordinates
    0,        // width of client area
    0,  
    hWnd1,
    NULL,    
    (HINSTANCE)GetWindowLong(hWnd1, GWL_HINSTANCE),
     NULL);
     SetWindowPos(
    richedit1,
    NULL,
    0,
    0,
    980,
    700,
    NULL);
if (!richedit1)
    {dw4=GetLastError();
      swprintf_s(dw5,100,L"%d",dw4);
                        MessageBox(hWnd1, dw5
                                   L"Error richedit",
                                   MB_OK);
         hwndButtonb = CreateWindow(
    L"BUTTON",  // Predefined class; Unicode assumed
    L"OK",      // Button text
    WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON,  // Styles
    380,         // x position
    265,         // y position
    25,        // Button width
    25,        // Button height
    richedit1,     // Parent window
    (HMENU) ID_BUTTONB,       // No menu.
    (HINSTANCE)GetWindowLong(richedit1, GWL_HINSTANCE),
    NULL);      // Pointer not needed.
    case WM_COMMAND:
        wmId    = LOWORD(wParam);
        wmEvent = HIWORD(wParam);
        // Parse the menu selections:
        switch (wmId)
            case IDM_OPEN:
       hr = CoInitializeEx(NULL, COINIT_APARTMENTTHREADED |
        COINIT_DISABLE_OLE1DDE);
    if (SUCCEEDED(hr))
          MessageBox(hWnd1, L"com is registered"
                                   L"Error 2",
                                   MB_OK);
        IFileOpenDialog *pFileOpen;
        hr = CoCreateInstance(CLSID_FileOpenDialog, NULL, CLSCTX_ALL,
                IID_IFileOpenDialog, reinterpret_cast<void**>(&pFileOpen));
        if (SUCCEEDED(hr))
            hr = pFileOpen->Show(NULL);
            if (SUCCEEDED(hr))
                IShellItem *pItem;
                hr = pFileOpen->GetResult(&pItem);
                if (SUCCEEDED(hr))
                    PWSTR pszFilePath;
                    hr = pItem->GetDisplayName(SIGDN_FILESYSPATH, &pszFilePath);
                    if (SUCCEEDED(hr))
                        MessageBox(NULL, pszFilePath, L"File Path", MB_OK);
    HANDLE hFile1 = CreateFile(pszFilePath, GENERIC_READ,
                              0, NULL, OPEN_EXISTING,
                              FILE_FLAG_SEQUENTIAL_SCAN, NULL);
if (hFile1 = INVALID_HANDLE_VALUE)
    {dwe=GetLastError();
      swprintf_s(dwe5,100,L"%d",dwe);
                        MessageBox(hWnd1, dwe5
                                   L"Error INVALID_HANDLE_VALUE",
                                   MB_OK);
  ReadFile(hFile1, &pbBuff1, sizeof(cb1), (DWORD *)&pcb1, NULL);
pcb1 = 0;
cb1 = 100;
dwCookie    = (DWORD_PTR)hFile1;
pfnCallback1 = NULL ;
dwError= 0;
pfnCallback1(dwCookie,pbBuff1,cb1,pcb1);
EDITSTREAM es1 = { 0 };
es1.pfnCallback = pfnCallback1;
es1.dwCookie    = (DWORD_PTR)hFile1;
es1.dwError =    dwError;
if (SendMessage(richedit1, EM_STREAMIN, SF_RTF, (LPARAM)&es1) && es1.dwError == 0)
CoTaskMemFree(pszFilePath);
        CloseHandle(hFile1);
                    pItem->Release();
            pFileOpen->Release();
        CoUninitialize();
            break;
        default:
            return DefWindowProc(hWnd1, message, wParam, lParam);
        break;
    case WM_PAINT:
        hdc = BeginPaint(hWnd1, &ps);
        // TODO: Add any drawing code here...
        EndPaint(hWnd1, &ps);
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    default:
        return DefWindowProc(hWnd1, message, wParam, lParam);
    return 0;
// Message handler for about box.
INT_PTR CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
    UNREFERENCED_PARAMETER(lParam);
    switch (message)
    case WM_INITDIALOG:
        return (INT_PTR)TRUE;
    case WM_COMMAND:
        if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL)
            EndDialog(hDlg, LOWORD(wParam));
            return (INT_PTR)TRUE;
        break;
    return (INT_PTR)FALSE;

Answer 1

You should post your question to the appropriate MSDN forum, as this forum is specific to questions regarding Microsoft Certifications.