🚀 go-pugleaf

In article <U=T.714494455@cansqnt> hlpell@sequent.com wrote:
> I want to have my software product prompt the user for his/her name and the
> registration number and then store this in a safe place, as do most
> software packages.  Can Visual Basic overwrite its own .EXE file to store
> this info?  That is, can I set aside an area of the .EXE that will be used
> exclusively for this purpose?  Then if the setup program sees that this
> area has data in it, it will not prompt the user to re-enter his/her name
> and registration number.
> 
> Any and all help appreciated.

Well, doing this gives me the heebee-geebies (is that how you spell that?)
but here you go:

Function ReplaceTextinEXE (EXE As String, Target As String, replace As String)
Dim f As Integer, i As Long, X As String
    If Len(Target) <> Len(replace) Then Exit Function
    f = FreeFile
    If UCase$(Right$(EXE, 4)) <> ".EXE" Then EXE = EXE + ".EXE"
    Open "foo.exe" For Binary Access Read Write Shared As f
    For i = 1 To LOF(f) - Len(Target)
        X = String$(Len(Target), " ")
        Get #f, i, X
        If X = Target Then
            Put #f, i, replace
            ReplaceTextinEXE = -1
            Close #f
            Exit Function
        End If
    Next
End Function


Essentially what you want to do is store a target string somewhere in
your application (an invisible label on a form, in the tag property of
any control, even as literal in your code).  Then you call this function 
and pass it the EXE name, the target string, and the replacement string.  
Obviously the target and replacement have to be the same length.  Also, 
since you don't have any control over the order that strings get put in 
the finished EXE, you want to make sure this string is unique so you 
replace the right one (and so this function will fail if you ever run 
it on the same EXE again). Notice too that this changes the file on
disk, not the copy in memory (if any).  So if you make the EXE modify
itself, you won't see the change until the next time you run it from
disk (moreover, you won't be able to run multiple instances of the app
--until you re-run it from disk--because the version in memory is different 
from the version on disk). For this reason you probably want to have a
separate "setup" program that writes into the EXE (this is what most
commercial applications do).

Like I said, actually writing into an EXE is a fairly risky thing to do.
Be careful.

Hope this helps.

--
Joe Robison
joero@microsoft.com
NAMS (Not A Microsoft Spokeshuman)