Private Function MakeScreenShot() As Bitmap
 
        Dim desk As String = My.Computer.FileSystem.SpecialDirectories.Desktop
 
        Dim Bmp As Bitmap = New Bitmap(Me.Width, Me.Height)
 
        Using Gra As Graphics = Graphics.FromImage(Bmp)
 
 
            Gra.CopyFromScreen(Me.Location.X, Me.Location.X, 0, 0, Me.Size)
        End Using
 
        Dim datum As String = Date.Now.Day & "/" & Date.Now.Month & "/" & _
          Date.Now.Year
        Dim Zeit As String = Date.Now.Hour & "/" & Date.Now.Minute & "/" & _
        Date.Now.Second
        Dim dateiname As String = datum & " " & Zeit
        Label21.Text = datum & " " & Zeit
        Bmp.Save(dateiname & "\" & "jpg", Imaging.ImageFormat.Jpeg)
        Return Bmp
 
 
    End Function

    Private Function MakeScreenShot() As Bitmap
 
        Dim desk As String = My.Computer.FileSystem.SpecialDirectories.Desktop
 
        Dim Bmp As Bitmap = New Bitmap(Me.Width, Me.Height)
 
        Using Gra As Graphics = Graphics.FromImage(Bmp)
            Gra.CopyFromScreen(Me.Location.X, Me.Location.X, 0, 0, Me.Size)
        End Using
 
        Dim datum As String = Date.Now.Day & "/" & Date.Now.Month & "/" & _
          Date.Now.Year
        Dim Zeit As String = Date.Now.Hour & "/" & Date.Now.Minute & "/" & _
        Date.Now.Second
 
        Dim dateiname As String = IO.Path.Combine(desk, datum & " " & Zeit & _
          ".jpg")
        dateiname = dateiname.Replace("/", "-")
 
        Label21.Text = datum & " " & Zeit
        Bmp.Save(dateiname, Imaging.ImageFormat.Jpeg)
        Return Bmp
 
 
    End Function

'Dateiname aus Datum erstellen
    Public Function fctDateiname(ByRef strdateiname As String) As String
        'erstellt einen Dateinamen aus dem aktuellen Datum
        'Genauigkeit: Datum + Stunde + Minute
        'Format: YYYYMMDD_hhmm
        Dim strDatum As String = CStr(DatePart("yyyy", Now))
        If Len(CStr(DatePart("m", Now))) = 1 Then
            strDatum = strDatum & "0" & CStr(DatePart("m", Now))
        Else
            strDatum = strDatum & CStr(DatePart("m", Now))
        End If
 
        If Len(CStr(DatePart("d", Now))) = 1 Then
            strDatum = strDatum & "0" & CStr(DatePart("d", Now))
        Else
            strDatum = strDatum & CStr(DatePart("d", Now))
        End If
 
 
        If Len(CStr(DatePart("h", Now))) = 1 Then
            strDatum = strDatum & "_0" & CStr(DatePart("h", Now))
        Else
            strDatum = strDatum & "_" & CStr(DatePart("h", Now))
        End If
 
        If Len(CStr(DatePart("n", Now))) = 1 Then
            strDatum = strDatum & "0" & CStr(DatePart("n", Now))
        Else
            strDatum = strDatum & CStr(DatePart("n", Now))
        End If
 
        strdateiname = strDatum
        Return strdateiname
    End Function

---
Verwendete Programmversionen:
Windows 7 64 bit sowie Windows 10 Prof.
Visual Studio 13 Professional
Microsoft Prof. 2010 (= Version 14)

Public Function FileNameNow(ByVal filename As String) As String
 
   Dim ext As String = IO.Path.GetExtension(filename)
   Dim fn As String = _
        filename.Substring(0, filename.Length - ext.Length)
 
   Return fn & Strings.Format(Now, "_yyyyMMdd_hhmm") & ext
 
End Function

---
Verwendete Programmversionen:
Windows 7 64 bit sowie Windows 10 Prof.
Visual Studio 13 Professional
Microsoft Prof. 2010 (= Version 14)

Public Function AdjustFilename(ByVal filename As String, _
                      Optional ByVal ReplaceChar As Char = "-"c) As String
 
   If String.IsNullOrWhiteSpace(filename) Then Return Nothing
 
   'Array der unzulässigen Zeichen im Dateinamen
   Dim ifnc As Char() = IO.Path.GetInvalidFileNameChars
 
   If ifnc.Contains(ReplaceChar) Then
      Throw New ArgumentException("Invalid ReplaceChar")
   End If
 
   Dim FileCharList As New System.Text.StringBuilder(filename)
 
   For i As Integer = 0 To FileCharList.Length - 1
      'unzulässige Zeichen ggf. ersetzen 
      If ifnc.Contains(FileCharList(i)) Then _
         FileCharList(i) = ReplaceChar
   Next i
 
   Return FileCharList.ToString
End Function