Q135818: How to List Available Drives from Visual FoxPro

Article: Q135818
Product(s): Microsoft FoxPro
Version(s): 
Operating System(s): 
Keyword(s): 
Last Modified: 19-AUG-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 3.0 
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SUMMARY
=======

This article shows by example how to determine which drive letters and types are
available on your computer. The sample code in this article can be used to list
the available drives and their types.

MORE INFORMATION
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The sample code in this article uses two API functions; DRIVETYPE() and
WNetGetConnection():

- DRIVETYPE(): The syntax for DRIVETYPE is:

  x = DRIVETYPE(<expC>)

  Here <expC> is the drive letter for which you want to know the drive
  type. DRIVETYPE() returns a numeric value representing the drive type of the
  drive . Possible return values are:

  0 - Drive does not exist
  1 - Drive has no root directory
  2 - Floppy Disk
  3 - Hard Disk
  4 - Removable or Network drive
  5 - CD-ROM
  6 - RAM Disk

  The DRIVETYPE function is included in FOXTOOLS.FLL. For more information on
  this function, please see FOXTOOLS.HLP in the VFP directory.

- WNetGetConnection(): When passed a valid network drive letter, the
  WNetGetConnection() function returns the name of the network resource. The
  syntax for WNetGetConnection() is:

  x = WNetGetConnection(lpszLocalName, lpszRemoteName, lpcchBuffer)

  Here lpszLocalName points to a buffer containing the local drive letter,
  lpszRemoteName points to a buffer that will receive the network resource name
  and lpcchBuffer points to a variable that contains the size, in characters,
  of the buffer pointed to by lpszRemoteName. WNetGetConnection is NOT part of
  FOXTOOLS.FLL, consequently before using this function you must declare it.
  For more information on this function see WIN32API.HLP.

Code Sample
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The following code sample echos to the desktop drive letters A through Z, and
displays the drive type of each. To run this example, open a new program (.prg)
file, enter the following code, and run it:

  ** BEGIN CODE SAMPLE
  SET LIBRARY TO \VFP\FOXTOOLS.FLL & Register the FOXTOOLS Library
  DECLARE INTEGER WNetGetConnection IN win32api ;
       STRING lpszLocalName,;
       STRING lpszRemoteName,;
       INTEGER @ lpchBuffer && Declare the external WNetGetConnection ;
       API function
  slpRemoteName = SPACE(254) && Initialize variables
  slen = LEN(slpRemoteName) && Initialize variables
  FOR I = 1 to 26 && Loop through drive letters A thru Z
       DRIVE = CHR(I + 64)
       DTYPE = DRIVETYPE(drive) && Determine drive type
       DO CASE
            CASE DTYPE = 0 && Non existent drives
                ? "Drive " + DRIVE + ": does not exist"
            CASE DTYPE = 1 && No root directory
                ? "Drive " + DRIVE + ": has no root directory"
            CASE DTYPE = 2 && Floppy drives
                 ? "Drive " + DRIVE + ": is a floppy drive"
            CASE DTYPE = 3 && Hard drives
                 ? "Drive " + DRIVE + ": is a local hard drive"
            CASE dtype = 4 && Removable or network drives
                 iSuccess = WNetGetConnection(drive + ;
                 ":",@slpRemoteName,@slen)
                 IF iSuccess = 0
                      ? "Drive " + Drive + ": is a network" + ;
                      " drive connected to " + LEFT(slpRemoteName,;
                      ATC(chr(0),slpRemoteName) - 1)
                 ENDIF
            CASE DTYPE = 5 && CD-ROM drives
                 ? "Drive " + DRIVE + ": is a CD ROM drive"
            CASE DTYPE = 6 && RAM drives
                 ? "Drive " + DRIVE + ": is a RAM drive"
       ENDCASE
  ENDFOR
  ** END CODE SAMPLE

Additional query words: VFoxWin

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP300

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