searching file, return string postion

[wordracr]

Is it possible to search a file for a string and return that string's position in the file?

Also, is it possible to read from X position to Z position in a file?

Thanks for your help!!!

[mikef]

use the Instr function.

[darre1]

yup, its a doddle.

just read the whole file into a string then use the Mid function to get the parts you want.

i.e.

Private Sub Form_Load()
    Dim strFile As String
    
    Open "C:\test.txt" For Binary As #1
        strFile = Input(LOF(1), #1)
    Close #1
    
    'this will display from character 10 to 19 (10 chars)
    MsgBox Mid$(strFile, 10, 10)
End Sub

[darre1]

also to find a string in a file:

Option Explicit
 
Private Sub FindInFile(strFilePath As String, strString As String)
    Dim strFile As String
    Dim lngPos As Long
    
    Open strFilePath For Binary As #1
        strFile = Input(LOF(1), #1)
    Close #1
    
    lngPos = InStr(strFile, strString)
    
    If lngPos > 0 Then
        MsgBox "'" & strString & "' found in file: " & strFilePath & " at character position " & lngPos
    Else
        MsgBox "'" & strString & "' not found in file: " & strFilePath
    End If
End Sub
 
Private Sub Form_Load()
    FindInFile "C:\test.txt", "bob"
End Sub

[mikef]

what's a doddle?

[darre1]

its british for "a piece of cake"

actually british for "a piece of cake" is "a piece of p!ss"

[mikef]

That's cool!!!

On the Great Race last night they had to figure out Australian slang.... I was totally confused!!!!

[darre1]

i guess that makes you a Wombat then?

[darre1]

oh and i do believe that our british version for that is Muppet

[mikef]

I used to watch the muppets on TV when I was kid.

[wordracr]

I thought a string could only hold 256 chars, but when I did a test label1.caption = strHTML, it has all the html. I'm not sure why my code won't work:

I can skip searching for text in a file if I can get this to work:

const strForm as String = "<form"
dim bytForms as Byte
Dim intPosition As Integer
intPosition = 0

bytForms = 0
'Gets number of forms in document
Do
intPosition = InStr(intPosition, strHTML, strForm)
If intPosition <> 0 Then
bytForms = bytForms + 1
End If
Loop Until intPosition = 0

This gives me a Run-Time error '5', Invalid procedure call or argument.
Any ideas?

[mikef]

Try this:

intPosition = 0

intForms = 0
'Gets number of forms in document
Do
  intPosition = InStr(intPosition + 1, strHTML, strForm)

  If intPosition <> 0 Then
    intForms = intForms + 1
  End If

  If intPosition = 0 Then Exit Do
Loop

MsgBox intForms

[wordracr]

I'll just answer my question =)

Strings can hold ~2 billion characters.

String positions start at 1, not 0 (like C++).

Thanks goes to all who helped...everyone does in someway.

[mikef]

That is what this does:

intPosition = InStr(intPosition + 1, strHTML, strForm)

intPosition = 0 but when you start the loop you add 1 to intPosition making it equal to 1....0 is considered a NULL value.... if you don't initialize it at 0 when you add 1 you would start at 2.

I tested you original code and found the errors.

Did you try the routine I posted. I did and it found all instances of <form.

...later

[darre1]

Originally posted by wordracr
I thought a string could only hold 256 chars

actually a variable length string variable can hold anything upto 2 billion characters according to MSDN