Way to free memory as I input lines from a file?

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From: Steven Douglas (theboydouglas_at_hotmail.com)
Date: 09/02/04 

Date: Thu, 2 Sep 2004 02:36:50 -0700

Hi,

I have some code where I open a very large file into
memory then enter a loop where I input each line one by
one, analyse it & draw data from it depending on certain
criteria.

The file being opened is 216,000 lines long and when the
code is running it just seems to get slower and slower
the further down the file it gets.

My question is, can I speed it up? I'm no expert, but
what I presume is happening is that Excel is, line by
line, opening more and more of the file into memory and
keeping it there. If that's the case, is there a way of
releasing the memory (of the lines) i no longer need?

I don't totally understand what the Filehandle & Freefile
things are, I just know that they work. In fact, would it
be quicker to use (Open openfile For Binary Access Read
As #Filehandle) & return data from the file that way?
(it's all the same place).

Any help on this would be greatly appreciated!

Thanks for your time,

Steven Douglas

Below is a very cut down version of the loop I'm running,
there are lot of other IF's & Do__Loop statements in
there, and I have them running as efficiently as possible.

'------------------------------------------------------

openfile = strDir & strBureau & "\XND.CSV"
Filehandle = FreeFile()

Open openfile For Input As #Filehandle

Do
Line Input #Filehandle, strData

 If Mid(strData, 2, 1) = "A" Then
  varkWh(1) = Mid(strData, 71, 8)
  varkWh(2) = Mid(strData, 55, 13)
  varkWh(3) = Mid(strData, 82, 30)
 End If

'CAN i PUT A LINE HERE TO RELEASE MEMORY

Loop Until EOF(1)
'------------------------------------------------------

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