Delete line from text file

That deleted the strings and the VBCRLF, but not the entire line.

Could you please post few sample lines having the strings.

1/13/2006 8:05:46 PM - (  1411) HOST domain:
1/13/2006 8:05:46 PM - (  1419) HOST domain:
1/13/2006 8:05:46 PM - (  1418) HOST domain:
1/13/2006 8:05:46 PM - (  1411) HOST domain:
1/13/2006 8:05:46 PM - (  1413) HOST domain:

Change the pattern to

oRegExp.Pattern = ".*Host Domain: .*\n"

It's been running now for about 15 min and hasn't made it through the first text file.

Ok, I killed it.  It was taking way too long.  I'll try #2.  Can you have 2 files open at the same time (1 for reading and 1 for writing)?

Yes.

Thanks.  I'll work on it.  When I ran it without writing to a file, I was able to run through quickly.  So I think that writing each line to a new file as I pass the line should go quickly.  Thanks again for the help.

I don't know what kind of machine you are running it at but I ran this on a file containing 100,000 lines and it completed in 3 seconds. I have a good machine but yours can't be that bad on any kind of machine. Also disk i/o is much slower compared to in memory comparision in any language. Thus reading and writing line by line would be much slower. Only when the RAM is running low, the in memory reading of file would translate to swap file writing and may cause the performace to degrade.

I noticed that the pattern still has an extra space in it. It should be

oRegExp.Pattern = ".*Host Domain:.*\n"

I went with this.  It works fine and takes less than a second to run through all my files.

Option Explicit

dim filepath, VBSName, objFSO, objTextFile, objTextFile2
dim fs, folder, file, item, line, fs1, filename

VBSname = wscript.scriptfullname

Filepath = left(VBSname, Len(VBSname) -(len(VBSname) - InstrRev(VBSname, "\")))

     set fs = CreateObject("Scripting.FileSystemObject")
     set folder = fs.GetFolder(FilePath)

     For each item in folder.Files
      If Right(item.name, 3) = "txt" Then

      Set objFSO = CreateObject("Scripting.FileSystemObject")
      Set objTextFile = objFSO.OpenTextFile (item, 1)
      Set fs1 = objFSO.CreateTextFile ("temp.txt",True)
      fs1.close
      Set objTextFile2 = objFSO.OpenTextFile ("temp.txt", 8)

      Do Until objTextFile.AtEndOfStream
          Line = objTextFile.ReadLine
            If InStr(1,Line, " Host Domain: ",1)  Then
            else
               objTextFile2.writeline line
            End If
      Loop

      set objTextFile = nothing
      set objTextFile2 = nothing

      filename = item.name

      objFSO.CopyFile "temp.txt", filename, true

      objFSO.DeleteFile "temp.txt"

      set objFSO = nothing
      Set fs1 = nothing

      End If
     next

msgbox "Done!"

The ReadAll should also take about the same (acuallty less but you probably won't be able to notice). I have done similar things several times and ReadAll has always performed better than reading line by line. In any case it can't take 15 minutes and still be not over. Something else must have happened at that time due to which either the script ran so slow or for some reason it might have hanged.

amit_g,

You are correct in saying that memory access is faster than hard drive access.

But vb is very slow at string manipulation.  If you use .ReadAll on a large file and then manipulate the resulting string, VB then has two make a copy in memory of the entire string.  Depending on what the system is doing this may take quite awhile.

Reading line by line may be slower for small files (and probably slower in general), but may make sense for larger files since it only has to deal with one line at a time.  It's a trade off...