c++完成的修改檔案名字尾

 #include <cstdlib>

#include <iostream>

#include <dirent.h>

#include <fcntl.h>

using namespace std;

int main(int argc, char *argv[])

{

    DIR *dirp=NULL;

    struct dirent *dp = NULL;

    char doing_file[1024];

    dirp = opendir("F:/Dev-Cpp/changename");

    FILE  *doing_fd;

    if(dirp == NULL)

  {

   printf("打開檔案失敗!/n/n");

   system("PAUSE");

            return EXIT_SUCCESS;

  }

    while( (dp = readdir(dirp)) != NULL )

  {

  // printf("..readdir:%s/n",dp->d_name);

      sprintf(doing_file,"%s",dp->d_name);

      string filename_old(doing_file); //改名前的檔案名

      string filename_new(doing_file); //改名後的檔案

      string::size_type point = filename_new.rfind("bmp");

      if(point != string::npos)

      {

                filename_new.replace(point,3,"jpg");

                if(rename(filename_old.c_str(),filename_new.c_str()) == 0)

                {

                   printf("改名成功完成/n/n");                                                 

                }

                else    

                perror("rename");    

            }

        } 

    closedir(dirp);

    system("PAUSE");

    return EXIT_SUCCESS;

}