取文件MD5 WINAPI

 #include <windows.h>
 #include <wincrypt.h>
 #include <stdio.h>

 BOOL GetFileHash(LPCSTR lpFileName, LPSTR lpHash)
 {
     BOOL bResult = FALSE;

     HANDLE hFile = CreateFile(lpFileName, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);

     if (hFile != INVALID_HANDLE_VALUE)
     {
         DWORD dwFileSize = GetFileSize(hFile, NULL);

         if (dwFileSize > )
         {
             PBYTE lpBuffer = (PBYTE)VirtualAlloc(NULL, dwFileSize, MEM_COMMIT, PAGE_READWRITE);

             if (lpBuffer != NULL)
             {
                 DWORD dwNumOfRead;

                 if (ReadFile(hFile, lpBuffer, dwFileSize, &dwNumOfRead, NULL) != FALSE)
                 {
                     HCRYPTPROV hProv;

                     if (CryptAcquireContext(&hProv, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT) != FALSE)
                     {
                         HCRYPTHASH hHash;

                         if (CryptCreateHash(hProv, CALG_MD5, NULL, NULL, &hHash) != FALSE)
                         {
                             if (CryptHashData(hHash, lpBuffer, dwFileSize, NULL) != FALSE)
                             {
                                 BYTE bData[]; DWORD dwDataLen;

                                 if (CryptGetHashParam(hHash, HP_HASHVAL, bData, &dwDataLen, NULL) != FALSE)
                                 {
                                     if (dwDataLen == )
                                     {
                                         LPSTR lpStr = lpHash;

                                         for (DWORD i = ; i < dwDataLen; i++, lpStr += )
                                         {
                                             sprintf(lpStr, "%02X", bData[i]);
                                         }

                                         bResult = TRUE;
                                     }
                                 }
                             }

                             CryptDestroyHash(hHash);
                         }

                         CryptReleaseContext(hProv, NULL);
                     }
                 }

                 VirtualFree(lpBuffer, , MEM_RELEASE);
             }
         }

         CloseHandle(hFile);
     }

     return bResult;
 }