usb memory stick

[stan58]

I want to develop a prog that would allow a user to write a recipe file consisting of several lines detailing product name and target weight values. To then transfer it to a USB memory stick that can be plugged into our weighing indicator product in order to control the formulation of a recipe. Is there any way of determining the path for the usb device and then do you just treat it like any other file?.

[Brandon Parker]

You can definitely treat the file path on a USB device (presumably a thumb-drive or hard-drive....) just like any other file path you might encounter.

Are you using a specific folder structure and file naming convention with your program?

You can use the code below to get started.....  Basically check to see if a specific folder and/ or file exists on each Drive that is installed in the system ....

The below is just a primer for you to see if you can work it out; let us know if you get stuck or otherwise require additional assistance.

'These are required for this code, but you can substitute the

'constant values for the global variables or use your own.

Global False : False = 0

Global True : True = 1



'Dimention the Double-Dimention Info$() Array for use

'with the Files command

Dim Info$(0, 0)



'Create our own variable for storing the information

'about which Drives are installed on the computer

'as to not mess around with the LB Drives$ variable

myInstalledDrives$ = Upper$(Drives$)



'See which Drives are installed

Print Drives$



'While Loop for checking each Drive installed for the folder you are looking for

While (Word$(myInstalledDrives$, (i + 1)) <> "")

   Scan    'Included here just in case one creates an Infinite Loop



   'Search each Drive for the folder where your file is expected to be

   'Your folder on the thumbdrive should be as unique as possible to ensure you do not get false positives.

   'Rename the folder you are looking for below; replace "Basic Languages" with your own

   If (searchForFolder(Word$(myInstalledDrives$, (i + 1)), "Basic Languages") > False) Then

       'You could do this first and just do this

       'Search for a specific file; replace the strings below with your specific ones or with variables as necessary

       If fileExists(Word$(myInstalledDrives$, (i + 1));"\Basic Languages", "myFileName.xxx")

           'Do something here like open the file or whatever....



       End If



   End If



   'Increment i to allow for moving along each of the installed Drives

   i = (i + 1)

Wend



End





'_________________________________________________________________________________________________________________________________________________________

'_________________________________________________________________________________________________________________________________________________________



   Function fileExists(path$, filename$)

       Files path$, filename$, Info$()

       fileExists = Val(Info$(0, 0))

       ReDim Info$(0, 0)

   End Function



'_________________________________________________________________________________________________________________________________________________________

'_________________________________________________________________________________________________________________________________________________________



   Function FileName$(name$)

       Do Until Instr(FileName$, "\", 1) > 0

           FileName$ = Mid$(name$, (Len(name$) - i))

           i = (i + 1)

       Loop

       FileName$ = Mid$(FileName$, 2)

   End Function



'_________________________________________________________________________________________________________________________________________________________

'_________________________________________________________________________________________________________________________________________________________



   Function FilePath$(name$)

       FilePath$ = Left$(name$, ((Len(name$) - Len(FileName$(name$))) - 1))

   End Function



'_________________________________________________________________________________________________________________________________________________________

'_________________________________________________________________________________________________________________________________________________________



   Function searchForFolder(directory$, folder$)

       On Error GoTo [Error]

           directory$ = directory$ + "\"

           Files directory$, "*", Info$()

           If Val(Info$(0,1)) > 0 Then

               For i = 1 To Val(Info$(0,1))

                   'Print Lower$(Info$(Val(Info$(0,0)) + i, 1));" : ";Lower$(folder$)

                   If Lower$(Info$(Val(Info$(0,0)) + i, 1)) = Lower$(folder$) Then

                       searchForFolder = True

                       Exit For

                   End If

               Next i

           End If

           ReDim Info$(0, 0)

       [Error]

   End Function



{:0)

Brandon R. Parker

[stan58]

Brendon
Thank you for your help,I will let you know how it goes.

[stan58]

Brendon
device$ = mid$ (Drives$,3,3)
print device$
end

Well I am a novice! just needed to know where the thumb drive is, your info sorted me.I can now make my folder in the USB device and then create
files.Is my code ok for clearing out the c: so that device$ holds my directory path

[Rod]

The one problem you might have is that Drive$() finds the available drives when the program starts. It will not report a USB drive inserted after the program has started. So you might need to cater for closing and restarting your program if the user has to be prompted to insert the USB drive mid program.

[stan58]

thank you Rod. That will save me scratching my head later.

[Brandon Parker]

Another thing you want to remember is that your USB device may not always be at that Drive Letter (ex. D: ). Windows can/ will shuffle things about and/ or give a device a different Drive letter due to a myriad of circumstances therefore you will need to search through the Drive Letters each time you start/ restart the program.


{:0)

Brandon R. Parker

[stan58]

path$= "d:"
on error goto [nodrive]
open path$+"testfile.txt" for output as #tst
print #tst,"hi"
close #tst
print "opened"

kill path$+"testfile.txt"
end
[nodrive]
print "no drive found"
end

Thought that I

[stan58]

path$= "d:"
on error goto [nodrive]
open path$+"testfile.txt" for output as #tst
print #tst,"hi"
close #tst
print "opened"

kill path$+"testfile.txt"
end
[nodrive]
print "no drive found"
end

Whoops pressed wrong button start again.
I thought that I could test the drives in sequence by trying to open a file if I was able to open the file ,then the drive is present.I would then kill the file,but for some reason I can make the file but not kill it ?

[Brandon Parker]

Normally you would have a "\" between the Drive Letter and the rest of the path. For some reason the file appears to be created perfectly fine without this in there, but the Kill command is definitely looking for it.

So...your path would be like this..

path$+"\testfile.txt"

Personally I would distinguish between the path and the filename, but everyone does things just a little different than the next person.


{:0)

Brandon R. Parker

[stan58]

Once again thank you. Is the principal of testing for drives in this way ok?

[Brandon Parker]

I would use the code that I posted above; checking for either the folder or the file (or both.... ). I typically try not to just create files and delete them where it is unnecessary.


{:0)

Brandon R. Parker

[stan58]

Thanks for your advice , also the backslash sorted my kill command.