String seperation with period

I have a string...

NewString(0) = "File1.txt"

I need to seperate it to

"file1"

But I dont need it stored ..
Just need to code so the
computer sees it without
storing it..

How can I do that?

Something like this:

If BeforePeriod(String1(0)) = "Text1" then
end if

Code:

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    Dim s As String
    s = "file1.txt"
    Debug.Print Strings.Left(s, InStr(1, s, ".") - 1)

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Code:

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Private Sub Command1_Click()

    NewString(0) = "File1.txt"
   
    If Left(NewString(0), 5) = "File1" Then
      MsgBox "Do Whatever"
    End If

End Sub

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Code:

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Dim intPeriodPos As Integer
Dim strTextBefPer As String

intPeriodPos = Instr(NewString(0), ".")
strTextBefPer = Left$(NewString(0), intPeriodPos - 1)
If strTextBefPer = "whatever" Then ...

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