取当前可用驱动器

返回值为一个字符串，形如'ABCD'

function myGetLogicalDrives : String;

var

  drives  : set of 0..25;

  drive   : integer;

begin

  Result := '';

  DWORD( drives ) := Windows.GetLogicalDrives;

  for drive := 0 to 25 do

     if drive in drives then

        Result := Result + Chr( drive + Ord( 'A' ));

end;

*********************

取的有效驱动器

API函数

DWORD GetLogicalDrives(VOID);

DWORD GetLogicalDriveStrings(

 DWORD nBufferLength,  // size of buffer

 LPTSTR lpBuffer      // drive strings buffer

);

UINT GetDriveType(

 LPCTSTR lpRootPathName  // root directory

);

******************

AvailableDrives :dword;

   AvailableDrives := GetLogicalDrives;

   for i:= 0 to 25 do

     if GetBit(AvailableDrives,i+1)=1 then//如果驱动器存在

     begin

       DrivePath:=Char(Ord('A')+i)+':\';

       case GetDriveType(pchar(DrivePath)) of

         DRIVE_FIXED :....//如果是硬盘

         DRIVE_......

       end;

     end;