XmlNode AppendChild works in C# but not VB.Net

I keep running into the below error message in vb.net, but in the same project done in C#, this works perfectly. After manually converting the project from C# to VB, this is where the error arises. Any suggestions would be appreciated.

Vb.Net:

Const App_ID As String = "WindowsToastTest"
Private Sub Button_Click(sender As Object, e As RoutedEventArgs)
' Get a toast XML template
Dim toastXml As XmlDocument = ToastNotificationManager.GetTemplateContent(ToastTemplateType.ToastImageAndText03)

' Fill in the text elements

Dim stringElements As XmlNodeList = toastXml.GetElementsByTagName("text")
For i As Integer = 0 To stringElements.Length
    stringElements(i).AppendChild(toastXml.CreateTextNode("Line " + i))
Next

' Specify the absolute path to an image
Dim imagePath As String = "file:///" + Path.GetFullPath("toastImageAndText.png")
Dim imageElements As XmlNodeList = toastXml.GetElementsByTagName("image")
imageElements(0).Attributes.GetNamedItem("src").NodeValue = imagePath

' Create the toast And attach event listeners
Dim toast As ToastNotification = New ToastNotification(toastXml)

' Show the toast. Be sure to specify the AppUserModelId on your application's shortcut!
ToastNotificationManager.CreateToastNotifier(APP_ID).Show(toast)

End Sub

C#:

namespace ToastSample

{

/// <summary>

/// Interaction logic for MainWindow.xaml

/// </summary>

public partial class MainWindow : Window

{

private const String APP_ID = “ToastSample”;

public MainWindow()

{

InitializeComponent();

}

private void Button_Click(object sender, RoutedEventArgs e)
{
    // Get a toast XML template
    XmlDocument toastXml = ToastNotificationManager.GetTemplateContent(ToastTemplateType.ToastImageAndText03);

    // Fill in the text elements
    XmlNodeList stringElements = toastXml.GetElementsByTagName("text");
    for (int i = 0; i &lt; stringElements.Length; i++)
    {
        stringElements[i].AppendChild(toastXml.CreateTextNode("Line " + i));
    }

    // Specify the absolute path to an image
    String imagePath = "file:///" + Path.GetFullPath("toastImageAndText.png");
    XmlNodeList imageElements = toastXml.GetElementsByTagName("image");
    imageElements[0].Attributes.GetNamedItem("src").NodeValue = imagePath;

    // Create the toast and attach event listeners
    ToastNotification toast = new ToastNotification(toastXml);

    // Show the toast. Be sure to specify the AppUserModelId on your application's shortcut!
    ToastNotificationManager.CreateToastNotifier(APP_ID).Show(toast);
}

}

}

#c-sharp #visual-basic.net