Преобразование из миллисекунд в формат DateTime

Один из способов сделать это с помощью кода ниже. XAML:

<Window x:Class="WpfApplication1.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:WpfApplication1"
Title="Window1" Height="300" Width="300" Loaded="Window_Loaded">
    <Canvas>
    </Canvas>
</Window>

C #:

using System.Windows;

using System.IO;
using System.Xml;
using System.Windows.Controls;

namespace WpfApplication1
{
    /// <summary>
    /// Interaction logic for Window1.xaml
    /// </summary>
    public partial class Window1 : Window
    {
        public Window1()
        {
            InitializeComponent();
        }

        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            double dWidth = -1;
            double dHeight = -1;
            FrameworkElement pnlClient = this.Content as FrameworkElement;
            if (pnlClient != null)
            {
                dWidth = pnlClient.ActualWidth;
                dHeight = pnlClient.ActualHeight;
            }
        }
    }
}