Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
  System.EventArgs) Handles Button1.Click
 
        Dim configurationAppSettings As System.Configuration.AppSettingsReader _
          = New System.Configuration.AppSettingsReader
 
        Dim connectionString As String = configurationAppSettings.GetValue( _
          "pfad4", GetType(System.String))
        Dim dbConnection As System.Data.IDbConnection = New _
        System.Data.SqlClient.SqlConnection(connectionString)
 
        Dim queryString As String = "SELECT TPM.Gerätetyp, Count(TPM.Gerätetyp)" & _
          "FROM TPM WHERE Datum BETWEEN '" & TB_FDate.Text & "' And '" & _
          TB_LDate.Text & "' GROUP BY TPM.Gerätetyp"
        Dim dbCommand As System.Data.IDbCommand = New _
        System.Data.SqlClient.SqlCommand
 
        dbCommand.CommandText = queryString
        dbCommand.Connection = dbConnection
        dbConnection.Open()
 
        Dim dataReader As System.Data.IDataReader = dbCommand.ExecuteReader()
        Do While dataReader.Read
 
            ReDim barrLabels(n)
            ReDim barrData(n)
 
 
            'ListBox1.Items.Add(dataReader.GetValue(0) & " || " & 
            ' dataReader.GetValue(1))
 
            barrLabels(n) = dataReader.GetValue(0)
            barrData(n) = dataReader.GetValue(1)
 
            ListBox1.Items.Add("array" & " " & n & " " & barrLabels(n)) _
              ' hier wird mir der gesamte inalt des arrays angezigt
            n = n + 1
        Loop
 
    End Sub

 Function bla()
        Dim i As Integer
        For i = 0 To n - 1
            ListBox1.Items.Add("array" & " " & i & " " & barrLabels(i))
        Next
 
    End Function