BOOL CFile::Open(LPCTSTR lpszFileName, UINT nOpenFlags,
    CFileException* pException)
{
    ASSERT_VALID(this);
    ASSERT(AfxIsValidString(lpszFileName));

    ASSERT(pException == NULL ||
        AfxIsValidAddress(pException, sizeof(CFileException)));
    ASSERT((nOpenFlags & typeText) == 0);   // text mode not supported

    // shouldn't open an already open file (it will leak)
    ASSERT(m_hFile == INVALID_HANDLE_VALUE);

    // CFile objects are always binary and CreateFile does not need flag
    nOpenFlags &= ~(UINT)typeBinary;

    m_bCloseOnDelete = FALSE;

    m_hFile = INVALID_HANDLE_VALUE;
    m_strFileName.Empty();

    TCHAR szTemp[_MAX_PATH];
    if (lstrlen(lpszFileName) < _MAX_PATH)
    {
        if( AfxFullPath(szTemp, lpszFileName) == FALSE )
            return FALSE;
    }
    else
        return FALSE; // path is too long
        
    m_strFileName = szTemp;

//    ASSERT(sizeof(HANDLE) == sizeof(UINT));
    ASSERT(shareCompat == 0);

    // map read/write mode
    ASSERT((modeRead|modeWrite|modeReadWrite) == 3);
    DWORD dwAccess = 0;
    switch (nOpenFlags & 3)
    {
    case modeRead:
        dwAccess = GENERIC_READ;
        break;
    case modeWrite:
        dwAccess = GENERIC_WRITE;
        break;
    case modeReadWrite:
        dwAccess = GENERIC_READ | GENERIC_WRITE;
        break;
    default:
        ASSERT(FALSE);  // invalid share mode
    }

    // map share mode
    DWORD dwShareMode = 0;
    switch (nOpenFlags & 0x70)    // map compatibility mode to exclusive
    {
    default:
        ASSERT(FALSE);  // invalid share mode?
    case shareCompat:
    case shareExclusive:
        dwShareMode = 0;
        break;
    case shareDenyWrite:
        dwShareMode = FILE_SHARE_READ;
        break;
    case shareDenyRead:
        dwShareMode = FILE_SHARE_WRITE;
        break;
    case shareDenyNone:
        dwShareMode = FILE_SHARE_WRITE | FILE_SHARE_READ;
        break;
    }

    // Note: typeText and typeBinary are used in derived classes only.

    // map modeNoInherit flag
    SECURITY_ATTRIBUTES sa;
    sa.nLength = sizeof(sa);
    sa.lpSecurityDescriptor = NULL;
    sa.bInheritHandle = (nOpenFlags & modeNoInherit) == 0;

    // map creation flags
    DWORD dwCreateFlag;
    if (nOpenFlags & modeCreate)
    {
        if (nOpenFlags & modeNoTruncate)
            dwCreateFlag = OPEN_ALWAYS;
        else
            dwCreateFlag = CREATE_ALWAYS;
    }
    else
        dwCreateFlag = OPEN_EXISTING;

    // special system-level access flags

    // Random access and sequential scan should be mutually exclusive
    ASSERT((nOpenFlags&(osRandomAccess|osSequentialScan)) != (osRandomAccess|
        osSequentialScan) );

    DWORD dwFlags = FILE_ATTRIBUTE_NORMAL;
    if (nOpenFlags & osNoBuffer)
        dwFlags |= FILE_FLAG_NO_BUFFERING;
    if (nOpenFlags & osWriteThrough)
        dwFlags |= FILE_FLAG_WRITE_THROUGH;
    if (nOpenFlags & osRandomAccess)
        dwFlags |= FILE_FLAG_RANDOM_ACCESS;
    if (nOpenFlags & osSequentialScan)
        dwFlags |= FILE_FLAG_SEQUENTIAL_SCAN;

    // attempt file creation
    HANDLE hFile = ::CreateFile(lpszFileName, dwAccess, dwShareMode, &sa,
        dwCreateFlag, dwFlags, NULL);
    if (hFile == INVALID_HANDLE_VALUE)
    {
        if (pException != NULL)
        {
            pException->m_lOsError = ::GetLastError();
            pException->m_cause =
                CFileException::OsErrorToException(pException->m_lOsError);

            // use passed file name (not expanded vesion) when reporting
            // an error while opening

            pException->m_strFileName = lpszFileName;
        }
        return FALSE;
    }
    m_hFile = hFile;
    m_bCloseOnDelete = TRUE;

    return TRUE;
}

UINT CFile::Read(void* lpBuf, UINT nCount)
{
    ASSERT_VALID(this);
    ASSERT(m_hFile != INVALID_HANDLE_VALUE);

    if (nCount == 0)
        return 0;   // avoid Win32 "null-read"

    ASSERT(lpBuf != NULL);
    ASSERT(AfxIsValidAddress(lpBuf, nCount));

    DWORD dwRead;
    if (!::ReadFile(m_hFile, lpBuf, nCount, &dwRead, NULL))
        CFileException::ThrowOsError((LONG)::GetLastError(), m_strFileName);

    return (UINT)dwRead;
}

/* Such a simple example */
    SOMETYPE buf;
    SOMETYPE * pTarget;
    if( NULL == ( fp = fopen("somefile", "rb") ) ){
        exit(1);
    }
    fread(pTarget, nSize, nHowmany, fp);
    /* ... */

    fclose(fp);

char *lsBuffer = NULL; 

char *lpFile = "file.jpg";
lpfp = fopen(lpFile, "rb"); 
if(lpfp == NULL)
   return;
struct stat stbuf;
stat(lpFile, &stbuf);
//用stat函数获取文件大小len 
int len = stbuf.st_size;
lsBuffer = new char[len + 1];
memset(lsBuffer, '\0', len + 1);

fread(lsBuffer, 1, len, lpfp); 
fclose(lpftp);

//处理lsBuffer里的数据
delete []lsBuffer

     // TODO: Place code here.
    FILE *fp;
    if((fp=fopen("\\saio\\user programs\\Zip.txt","r+" ))==NULL)
    {
        printf("Can not open file.\n");
    }
    //////////////////////////////////////////
    //把文件的位置指针移到文件尾
    fseek(fp,0L,SEEK_END);
    //获取文件长度;
    long length=ftell(fp);
    ///////////////////////////////////////////
    
    // create a source buffer
    BYTE *source = (BYTE*)LocalAlloc(LPTR, length);
    BYTE *compressed = NULL;

    if (source == NULL)
    {
        return -1;
    }
    // the compress algorithm looks for repeat sequences, so generate data that has that
    srand(GetTickCount());    

    fseek(fp, 0L, SEEK_SET);
    fread(source, 1, length , fp);

    fclose(fp);

//先把int nData[10];保存为二进制文件，后读出
#include "stdio.h"
#include <stdlib.h>
int average(char *pFilePath);
void main()
{
    FILE *fp;
    int nData[10];
    for(int i=0;i<10;i++)
    {
        printf("请输入第%d个数:",i+1);
        scanf("%d",nData+i);
    }
    fp = fopen("c:\\data.txt", "wb");//b表示以二进制的形式写入文件
    if(fp!=NULL)
    {
        fwrite(nData,sizeof(int),10,fp);
        fclose(fp);
        //写完文件后，可以看一下文件大小，40个字节，
        //其实就是数组的大小  sizeof(int)*10 = 40   以前在学校里没搞明白的问题，现在明白了
    }

    printf("平均值大小:%d\n",average("c:\\data.txt") );


    system("pause");
}

int average(char *pFilePath)
{
    int nData[10]={0};
    FILE *fp;
    fp = fopen(pFilePath, "rb");//b表示以二进制的形式
    if(fp!=NULL)
    {
        fread(nData,sizeof(int),10,fp);
        fclose(fp);    
    }
    else
    {
        printf("读取文件出错了...");
        return 0 ;
    }

    int nSum = 0 ;
    for(int i=0;i<10;i++)
    {
        printf("第%d个数:\t内存地址%8x\t值:%d\n",i+1,nData+i,*(nData+i));
        nSum += *(nData+i) ;
    }
    return nSum/10;
}