vc提供的遍历目录的函数 FindFirstFile

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VC声明

　　HANDLE FindFirstFile(　　LPCTSTR lpFileName, // file name　　LPWIN32_FIND_DATA lpFindFileData // data buffer　　);

功能说明

　　该函数到一个文件夹(包括子文件夹)去搜索指定文件如果要使用附加属性去搜索文件的话可以使用FindFirstFileEx函数

参数说明

　　HANDLE hFindFile搜索的文件句柄函数执行的时候搜索的是此句柄的下一文件　　LPWIN32_FIND_DATA lpFindFileData 指向一个用于保存文件信息的结构体

返回值

　　如果调用成功返回一个句柄，可用来做为FindNextFile或FindClose参数　　调用失败返回为INVALID_HANDLE_VALUE(即-1) ,可调用GetLastError来获取错误信息

在此要注意的是返回为INVALID_HANDLE_VALUE时表明的是调用函数失败

上msdn上的代码一目了然：

#include <windows.h>
#include <tchar.h>
#include <stdio.h>
#include <strsafe.h>

void DisplayErrorBox(LPTSTR lpszFunction);

int _tmain(int argc, TCHAR *argv[])
{
     WIN32_FIND_DATA ffd;
     LARGE_INTEGER filesize;
     TCHAR szDir[MAX_PATH];
     size_t length_of_arg;
     HANDLE hFind = INVALID_HANDLE_VALUE;
     DWORD dwError=0;

     // If the directory is not specified as a command-line argument,
     // print usage.

     if(argc != 2)
     {
        _tprintf(TEXT("\nUsage: %s <directory name>\n"), argv[0]);
        return (-1);
     }

     // Check that the input path plus 3 is not longer than MAX_PATH.
     // Three characters are for the "\*" plus NULL appended below.

     StringCchLength(argv[1], MAX_PATH, &length_of_arg);

     if (length_of_arg > (MAX_PATH - 3))
     {
        _tprintf(TEXT("\nDirectory path is too long.\n"));
        return (-1);
     }

     _tprintf(TEXT("\nTarget directory is %s\n\n"), argv[1]);

     // Prepare string for use with FindFile functions. First, copy the
     // string to a buffer, then append '\*' to the directory name.

     StringCchCopy(szDir, MAX_PATH, argv[1]);
     StringCchCat(szDir, MAX_PATH, TEXT("\\*"));

     // Find the first file in the directory.

     hFind = FindFirstFile(szDir, &ffd);

     if (INVALID_HANDLE_VALUE == hFind)
     {
        DisplayErrorBox(TEXT("FindFirstFile"));
        return dwError;
     }

     // List all the files in the directory with some info about them.

     do
     {
        if (ffd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
        {
           _tprintf(TEXT(" %s   <DIR>\n"), ffd.cFileName);
        }
        else
        {
           filesize.LowPart = ffd.nFileSizeLow;
           filesize.HighPart = ffd.nFileSizeHigh;
           _tprintf(TEXT(" %s   %ld bytes\n"), ffd.cFileName, filesize.QuadPart);
        }
     }
     while (FindNextFile(hFind, &ffd) != 0);

     dwError = GetLastError();
     if (dwError != ERROR_NO_MORE_FILES)
     {
        DisplayErrorBox(TEXT("FindFirstFile"));
     }

     FindClose(hFind);
     return dwError;
}

void DisplayErrorBox(LPTSTR lpszFunction)
{
      // Retrieve the system error message for the last-error code

      LPVOID lpMsgBuf;
      LPVOID lpDisplayBuf;
      DWORD dw = GetLastError();

      FormatMessage(
          FORMAT_MESSAGE_ALLOCATE_BUFFER |
          FORMAT_MESSAGE_FROM_SYSTEM |
          FORMAT_MESSAGE_IGNORE_INSERTS,
          NULL,
          dw,
          MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
          (LPTSTR) &lpMsgBuf,
          0, NULL );

      // Display the error message and clean up

      lpDisplayBuf = (LPVOID)LocalAlloc(LMEM_ZEROINIT,
          (lstrlen((LPCTSTR)lpMsgBuf)+lstrlen((LPCTSTR)lpszFunction)+40)*sizeof(TCHAR));
      StringCchPrintf((LPTSTR)lpDisplayBuf,
          LocalSize(lpDisplayBuf) / sizeof(TCHAR),
          TEXT("%s failed with error %d: %s"),
          lpszFunction, dw, lpMsgBuf);
      MessageBox(NULL, (LPCTSTR)lpDisplayBuf, TEXT("Error"), MB_OK);

      LocalFree(lpMsgBuf);
      LocalFree(lpDisplayBuf);
}

用这个遍历目录稍微改一下就可以用在程序里了

贴上某牛人的研究：

今天终于试验出FindFirstFile的正确用法

void CFindFilesDlg::OnBnClickedButton1()
{
// TODO: 在此添加控件通知处理程序代码
CString c1;
CString stredit;
CString strtemp;
HANDLE hFile;
WIN32_FIND_DATA fileinfo;
DWORD errorcode = 0;
m_Edit1.GetWindowText(c1);   //要熟悉控件的基本使用
if(!c1.IsEmpty())
{
       hFile=FindFirstFile("f:\\*.*",&fileinfo);
    while(hFile!=INVALID_HANDLE_VALUE&&errorcode!=ERROR_NO_MORE_FILES)
    {
     //
   strtemp=fileinfo.cFileName;
   stredit=stredit+"\r\n";
   stredit=stredit+strtemp;
   FindNextFile(hFile,&fileinfo);
   errorcode=GetLastError();
    }
    if(errorcode==ERROR_NO_MORE_FILES)
    {
     m_cedit1.SetWindowText(stredit);
     MessageBox("检索结束");
    }
    CloseHandle(hFile);
}
}