WPF Application Error: BC30002 Type PrintWindow is not defined in VB.Net

This way

1. Create a PrintDialog: Instantiate a PrintDialog object.
2. Show the dialog: Call ShowDialog() on the PrintDialog to display the print dialog box. This allows the user to select a printer and configure print settings.
3. Print the visual: If the user selects "OK" in the print dialog, call PrintVisual on the PrintDialog object, passing the window (or any other visual element) as the visual to be printed and a descriptive string for the job.

using System.Windows;
using System.Windows.Controls;

namespace PrintingExample
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void PrintButton_Click(object sender, RoutedEventArgs e)
        {
            PrintDialog printDialog = new PrintDialog();
            if (printDialog.ShowDialog() == true)
            {
                printDialog.PrintVisual(this, "My Window");
            }
        }
    }
}

<Window x:Class="PrintingExample.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <Button Content="Print" Click="PrintButton_Click" HorizontalAlignment="Center" VerticalAlignment="Center"/>
    </Grid>
</Window>