if a = b then
   Textbox1.Text="Test"
end if

Dim fls() As IO.FileInfo = New IO.DirectoryInfo(...).GetFiles("*.ta") 
For Each fs As IO.FileInfo In fls 
If fs.Name.Substring(2, 6) = ds Then 
Dim Reader2 As New IO.StreamReader(fs.FullName, System.Text.Encoding.Default) 
Dim line As String 
 
Dim strTeile() As String 
Dim intLetzte As Integer = 0 
Dim j As Integer = 0 
 
While Reader2.Peek() > 0 
 
line = Reader2.ReadLine 
If line = "" Then 
' wenn er hier ankommt, soll die nächste Datei aus dem Ordner gelesen werden 
End If 
 
s = line.Substring(0, 78) 
writer.WriteLine(s) 
 
dr = dt.NewRow() 
dr(0) = line.Substring(0, 5) 
dr(1) = line.Substring(6, 3) 
dt.Rows.Add(dr) 
 
End While 
 
reader2.Close() ' Fehlt! 
End If ' Fehlt! 
Next 'Fehlt! 
 
DataGrid1.DataSource = New DataView(dt)

Dim fls() As IO.FileInfo = New IO.DirectoryInfo(...).GetFiles("*.ta") 
For Each fs As IO.FileInfo In fls 
   If fs.Name.Substring(2, 6) = ds Then 
      Dim Reader2 As New IO.StreamReader(fs.FullName, _
        System.Text.Encoding.Default) 
      Dim line As String 
 
      Dim strTeile() As String 
      Dim intLetzte As Integer = 0 
      Dim j As Integer = 0 
 
        While Reader2.Peek() > 0 
 
           line = Reader2.ReadLine 
           If line <>  "" Then 
 
              s = line.Substring(0, 78) 
              writer.WriteLine(s) 
 
              dr = dt.NewRow() 
              dr(0) = line.Substring(0, 5) 
              dr(1) = line.Substring(6, 3) 
              dt.Rows.Add(dr) 
           end if
        End While 
 
        reader2.Close() ' Fehlt! 
   End If ' Fehlt! 
Next 'Fehlt! 
 
DataGrid1.DataSource = New DataView(dt)