'Überprüft die Verfügbarkeit einer WebSite
    Public Function checkState(ByVal url As String) As Boolean
        Dim request As System.Net.WebRequest
        Dim response As System.Net.WebResponse
        Dim bConnected As Boolean = False
        Try
            request = System.Net.WebRequest.Create(url)
            request.Timeout = 10000
            response = CType(request.GetResponse(), System.Net.HttpWebResponse)
            If [...] Then
                bConnected = True
            End If
 
            request.Abort()
            response.Close()
        Catch ex As Exception
            bConnected = False
        Finally
            request = Nothing
            response = Nothing
        End Try
 
        Return bConnected
    End Function