各位大虾能否帮我解释一下如下函数主要是声明变量部分和标记的部分多谢多谢

TDateTime TForm1::GetFileTime(String sFilename,int TimeType)
//自定义GetFileTime，该函数用来获取文件时间信息
   {
         WIN32_FIND_DATA ffd;
         WORD fd,ft;
         DWORD fdt;
         FILETIME  lft,Time;
         HANDLE H;
     
      H=FindFirstFile(sFilename.c_str(),&ffd);
         switch(TimeType)
         {
             case 0:Time=ffd.ftCreationTime;     break;    
            case 1:Time=ffd.ftLastWriteTime;    break;   
             case 2:Time=ffd.ftLastAccessTime;   break;   
           default:
                    Time=ffd.ftCreationTime;
           }
“××××”     if(H!=INVALID_HANDLE_VALUE)                            {
                 FindClose(H);                         
                 FileTimeToLocalFileTime(&Time,&lft);
                 FileTimeToDosDateTime(&lft,&fd,&ft);  
                 return FileDateToDateTime(MAKELONG(ft,fd));
             }
            else
                 return TDateTime();    
     }