写程序的时候遇到一点困难，怎样得知驱动器中有没有插入盘？譬如插入SD卡的移动存储器？  

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你用这个函数试试DeviceIoControl：  

 

IOCTL_STORAGE_CHECK_VERIFY  

The  IOCTL_STORAGE_CHECK_VERIFY  DeviceIoControl  operation  determines  whether  a  device's  media  is  accessible;  for  example,  whether  the  media  is  in  the  device.    

 

BOOL  DeviceIoControl(  

    (HANDLE)  hDevice,                //  handle  to  device  of  interest  

    IOCTL_STORAGE_CHECK_VERIFY,    //  dwIoControlCode,  control  code  of  

                                                      //  operation  to  perform  

    NULL,                                        //  lpInBuffer  is  not  used;  must  be  NULL  

    0,                                              //  nInBufferSize  is  not  used;  must  be  zero  

    NULL,                                        //  lpOutBuffer  is  not  used;  must  be  NULL  

    0,                                              //  nOutBufferSize  is  not  used;  

                                                      //  must  be  zero  

    (LPDWORD)  lpBytesReturned,      //  pointer  to  variable  to  receive  

                                                      //  output  byte  count  

    (LPOVERLAPPED)  lpOverlapped    //  pointer  to  OVERLAPPED  structure  

                                                      //  for  asynchronous  operation  

);  

 

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bool  IsMediaExist(char  *Drive)  

{  

            char                        DeviceName[MAX_PATH];  

            HANDLE                        hDevice;  

            DWORD                        cbBytesAct  =  0;  

            bool                        fMediaExist  =  false;  

 

            sprintf(DeviceName,  "\\\\.\\%s",  Drive);  

 

            hDevice  =  CreateFile(  

                        DeviceName,  

                        GENERIC_READ    &brvbar  GENERIC_WRITE,  

                        FILE_SHARE_READ,  

                        NULL,  

                        OPEN_EXISTING,  

                        NULL,  

                        NULL);  

 

            if  (hDevice  !=  INVALID_HANDLE_VALUE)  {  

                        if  (DeviceIoControl(  

                                    hDevice,  

                                    IOCTL_DISK_CHECK_VERIFY,  

                                    NULL,  

                                    0,  

                                    NULL,  

                                    0,  

                                    &cbBytesAct,  

                                    NULL))  {  

                                    fMediaExist  =  true;  

                        }  

 

                        CloseHandle(hDevice);  

            }  

 

            return(  fMediaExist  );  

}