Private Sub Application_Startup(ByVal o As Object, _
    ByVal e As StartupEventArgs) Handles Me.Startup

    Dim p As New Page
    Me.RootVisual = p

    ' This assumes that Page.LayoutRoot exists and is a StackPanel.
    Dim layoutRoot As StackPanel = p.LayoutRoot

    ' Display the custom initialization parameters.
    For Each key As String In e.InitParams.Keys
        layoutRoot.Children.Add(New TextBlock With { _
            .Text = String.Format( _
                "from InitParams: {0} = {1}", _
                key, e.InitParams(key))})
    Next

    ' Display the URL parameters.
    For Each key As String In HtmlPage.Document.QueryString.Keys
        layoutRoot.Children.Add(New TextBlock With { _
            .Text = String.Format( _
                "from QueryString: {0} = {1}", key, _
                HtmlPage.Document.QueryString(key))})
    Next

End Sub

private void Application_Startup(object sender, StartupEventArgs e)
{
    Page p = new Page();
    this.RootVisual = p;

    // This assumes that Page.LayoutRoot exists and is a StackPanel.
    StackPanel layoutRoot = p.LayoutRoot; 

    // Display the custom initialization parameters.
    foreach (String key in e.InitParams.Keys)
    {
        layoutRoot.Children.Add(new TextBlock() {
            Text = String.Format(
                "from InitParams: {0} = {1}", key, 
                e.InitParams[key])
        });
    }

    // Display the URL parameters.
    foreach (String key in HtmlPage.Document.QueryString.Keys)
    {
        layoutRoot.Children.Add(new TextBlock()
        {
            Text = String.Format(
                "from QueryString: {0} = {1}", key, 
                HtmlPage.Document.QueryString[key])
        });
    }            
}