Finding text in a large file

[altinbay]

Is there a way to find text within a large file (several megabytes)? I'm trying to find out if a chm file contains a topic, and it looks like the topics are listed at the top. Alternatively, if there is something that allows me to find this out, rather than open a dialog with "page not found" displayed, that would work to solve my problem.
Thanks in advance.

[Iouri]

Look at this code. It might help you

Find and replace a string in all files matching a pattern
in a directory

Use Dir$ to find the files. For each file, read the file and use Replace
to make the replacement.

Note that the find or replace text can contain carriage returns.


Private Sub cmdReplace_Click()
Dim from_text As String
Dim to_text As String
Dim dir_name As String
Dim patterns As Variant
Dim file_name As String
Dim i As Integer
Dim results As String

' Get the text to find and replace.
from_text = txtFind.Text
to_text = txtReplace.Text

' Get the directory name.
dir_name = FileList.Path
If Right$(dir_name, 1) <> "\" Then dir_name = dir_name & "\"

' Get the file patterns.
patterns = Split(FileList.Pattern, ";")

results = "Files:"

' Repeat for each pattern.
For i = LBound(patterns) To UBound(patterns)
' Add the pattern to the file name.
file_name = Dir$(dir_name & patterns(i))
Do While Len(file_name) > 0
' Process this file.
results = results & " " & file_name
ReplaceInFile dir_name & file_name, from_text, to_text

' Get the next file.
file_name = Dir$()
Loop
Next i

MsgBox results
End Sub

' In the file file_name, replace occurrances of from_text
' with to_text.
Private Sub ReplaceInFile(ByVal file_name As String, ByVal from_text
As String, ByVal to_text As String)
Dim fnum As Integer
Dim file_text As String

' Read the file.
fnum = FreeFile
Open file_name For Input As fnum
file_text = Input$(LOF(fnum), #fnum)
Close #fnum

' Replace the text.
file_text = Replace(file_text, from_text, to_text)

' Rewrite the file.
fnum = FreeFile
Open file_name For Output As fnum
Print #fnum, file_text
Close #fnum
End Sub






Iouri Boutchkine
iouri@hotsheet.com

[altinbay]

Thanks for the quick response.

The file I am looking at is 3Mb. Wouldn't reading it into a string be bad news?

[Cimperiali]

Here how to quick retrieve the content of a file in binary mode

http://codeguru.com/cgi-bin/bbs/wt/showpost.pl?Board=vb&Number=62963&page=&view=&sb=

You can then search in the result array for what you need.
This should be quicker in opening and retrieving data.


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