Fastest FSO loop question

[David P. Jessup]

Well I have seen this posted before and haven't seen much in response.

My application has to browse through various folders and find file names.
Sometimes these folders can have thousands of files in them, and of course
looping through each file to find the right one can take a bit of time.

I'm using classic ASP and was wondering if there are any other methods
available to speed up this process other than hardware upgrades.

My application does a search based on an "index" number. All files start
with this index number but might have different file extentions. It then
displays the all the files for the queried index. The requirement is to
display all the files for a given index, not just a specific file.
example:
1234 file.doc
1234 file.jpg
1234 file.pdf

Code:
For Each fl in fc
fileIndex = Left(fl.name,In Str(fl.name," "))
if fileIndex = findex & " " Then
Response.write ("|<a href ='" & webpath & fl.name & "' >" & fl.name &
"</a>|")
End if
Next

I have read here that using WITH can speed this up but I haven't been able
to see any real improvement.

Code:
with response
For Each fl in fc
fileIndex = Left(fl.name,In Str(fl.name," "))
if fileIndex = findex & " " Then
Response.write ("|<a href ='" & webpath & fl.name & "' >" & fl.name &
"</a>|")
End if
Next
end with

Any other tips or tricks would be appreciated.

Thanks from this ASP newbie

[Randy Rahbar]

> I have read here that using WITH can speed this up but I haven't been able

to see any real improvement.

Code:
with response
For Each fl in fc
fileIndex = Left(fl.name,In Str(fl.name," "))
if fileIndex = findex & " " Then
Response.write ("|<a href ='" & webpath & fl.name & "' >" & fl.name &
"</a>|")
End if
Next
end with

When you use "with response", you should be able to leave out the "Response"
when you're writing the line...

Response.write ("|<a href ='" & webpath & fl.name & "' >" & fl.name &
"</a>|")
should become
..write ("|<a href ='" & webpath & fl.name & "' >" & fl.name & "</a>|")

I'm not sure this will speed up this process much though.

[Ray at]

I don't know that this would be the best solution, but I'd at least try it:

Dim sDirRoot, sOutputFile, sSearch, sFileList
sDirRoot = "D:\ThePathOnYo urServerWithThe FilesYouWantToS ee\"
sSearch = "1234"
sOutputFile = "D:\SomePathOnY ourServer\" & sSearch & ".txt"
'''run dir C:\path\1234* and pipe out to a file
Server.CreateOb ject("WScript.S hell").Run "cmd.exe /c dir /B " & sDirRoot &
sSearch & "*>" & sOutputFile, 0, True
sFileList =
Server.CreateOb ject("Scripting .FileSystemObje ct").OpenTextFi le(sOutputFile,
1).ReadAll
That would then leave you with a list like:
1234 file.doc
1234 file.jpg
1234 file.pdf

in a string variable, and you can do with it what you like then.

Permissions for writing the output file and executing cmd.exe would need to
be considered.
Two people accessing the page at the same time would need to be considered.
(You may even want to only have a new output file created if an existing one
is older than a certain date, depending on your needs, or you may want to
generate random filenames by session to avoid overwrites.)

Ray at work


"David P. Jessup" <davidATimntDAS HtechDOTcom> wrote in message
news:eC******** *****@tk2msftng p13.phx.gbl...

Well I have seen this posted before and haven't seen much in response.

My application has to browse through various folders and find file names.
Sometimes these folders can have thousands of files in them, and of course
looping through each file to find the right one can take a bit of time.

I'm using classic ASP and was wondering if there are any other methods
available to speed up this process other than hardware upgrades.

My application does a search based on an "index" number. All files start
with this index number but might have different file extentions. It then
displays the all the files for the queried index. The requirement is to
display all the files for a given index, not just a specific file.
example:
1234 file.doc
1234 file.jpg
1234 file.pdf

[Aaron Bertrand - MVP]

> '''run dir C:\path\1234*

Might also add /b switch to the dir command (brief) for a wee bit of
efficiency.

[Ray at]

I did include the /B.

Ray at work

"Aaron Bertrand - MVP" <aa***@TRASHasp faq.com> wrote in message
news:OR******** ******@tk2msftn gp13.phx.gbl...

'''run dir C:\path\1234*

Might also add /b switch to the dir command (brief) for a wee bit of
efficiency.

[Aaron Bertrand - MVP]

Sorry, I was looking at THIS line, which did not:

'''run dir C:\path\1234* and pipe out to a file

I did include the /B.

[Ray at]

I comment miserably... Most of my comments are completely useless and only
say things like:

''The code below is completely idiotic, but I don't have time to do things
right.

Excuses, excuses...

Ray at work

"Aaron Bertrand - MVP" <aa***@TRASHasp faq.com> wrote in message
news:%2******** ********@TK2MSF TNGP09.phx.gbl. ..

Sorry, I was looking at THIS line, which did not:

'''run dir C:\path\1234* and pipe out to a file

I did include the /B.

[Aaron Bertrand - MVP]

> I comment miserably...

Yep.

Oh, you mean in code. Ahhh. Ok.

;-)

[Alan]

Also, if you use one of the last two options you could do something like
(shown for option three):

For Each fl in fc

fileName = fl.name ' copy property to local variable - faster??

' If the length of your index is constant (0000-9999 maybe) then define
this outside of the For Each loop.
' If the length varies by file (e.g. 0-9999) then leave it here.
MaxLevels = InStr (fileName, " ") - 1 ' this gets rid of one call to
'Left' per file.

For Level = 1 to MaxLevels
If (Left (fileName, Level) = Left (findex, Level)) Then
Response.write ("|<a href ='" & webpath & fl.name & "'" &
fl.name & "</a>|")
End If
Next

Next

Try that too :)

Alan

"Alan" <SP************ ******@inspire. net.nz> wrote in message
news:#K******** ******@TK2MSFTN GP12.phx.gbl...

I'm going to do you a disservice here and NOT back up any of these
suggestions with experimental code or timings or anything - I don't even
know if my assumptions are accurate. I'm going to use the weak excuse of
having too many clients that want me to do work for them instead:) I would
be really interested in your results though, if you, say, populated a
directory with a few thousand of these files and tried the approaches that
people have suggested.

For Each fl in fc
fileIndex = Left(fl.name,In Str(fl.name," "))
if fileIndex = findex & " " Then
Response.write ("|<a href ='" & webpath & fl.name & "' >" & fl.name & "</a>|")
End if
Next
1. Remove the spaces:

if fileIndex = findex & " " Then

Don't concatenate the space. Instead remove the trailing space from
fileIndex. Also, the subtype of these vars is probably String at the

moment (because of the space) - get rid of the space and then:

2. Cast subtypes to Int:

Perhaps integer comparison is faster than string comparison. Assuming no
space:

if (CInt (fileIndex) = CInt (findex)) Then
3. Progressive Checking:

I don't know how these files indexes are used or what typical search
criteria are, but assuming a sequential ordering you could try

progressively checking to see if the fileIndex matches. This would mean fewer checks at
each level before the algorithm gets a chance to move on. Again, you'd have to experiment with string and integer comparisons. This is gash but you get the idea:

For Each fl in fc

fileName = fl.name
fileIndex = Left (fileName, InStr(fl.name," ")-1)

If (Left (fileName, 1) = Left (findex, 1)) Then
If (Left (fileName, 2) = Left (findex, 2)) Then
If (Left (fileName, 3) = Left (findex, 3)) Then
If (Left (fileName, 4) = Left (findex, 4)) Then
Response.write ("|<a href ='" & webpath & fl.name & "'

" & fl.name & "</a>|") End If
End If
End If
End if
Next

4. Compare next char only:

Vary the previous method to only check each subsequent char/int instead of
the previously checked ones too. That is, instead of using Left (findex,

2) in the second conditional, just check the second char in findex - you
already know the first char is a match. This will depend on the efficiency
of Left cf. something like Instr.

Make sure you let us know how you go.

Alan

"David P. Jessup" <davidATimntDAS HtechDOTcom> wrote in message
news:eC******** *****@tk2msftng p13.phx.gbl...

Well I have seen this posted before and haven't seen much in response.

My application has to browse through various folders and find file names. Sometimes these folders can have thousands of files in them, and of course looping through each file to find the right one can take a bit of time.

I'm using classic ASP and was wondering if there are any other methods
available to speed up this process other than hardware upgrades.

My application does a search based on an "index" number. All files start with this index number but might have different file extentions. It then
displays the all the files for the queried index. The requirement is to
display all the files for a given index, not just a specific file.
example:
1234 file.doc
1234 file.jpg
1234 file.pdf

Code:
For Each fl in fc
fileIndex = Left(fl.name,In Str(fl.name," "))
if fileIndex = findex & " " Then
Response.write ("|<a href ='" & webpath & fl.name & "' >" & fl.name & "</a>|")
End if
Next

I have read here that using WITH can speed this up but I haven't been able to see any real improvement.

Code:
with response
For Each fl in fc
fileIndex = Left(fl.name,In Str(fl.name," "))
if fileIndex = findex & " " Then
Response.write ("|<a href ='" & webpath & fl.name & "' >" & fl.name & "</a>|")
End if
Next
end with

Any other tips or tricks would be appreciated.

Thanks from this ASP newbie