WPF

<br />
        [Required(ErrorMessage="User Name is Required")]<br />
        [StringLength(12,MinimumLength=6,ErrorMessage="User Name must be in between 6 to 12 Characters")]<br />
        public string UserName<br />
        {<br />
            get { return _UserName; }<br />
            set <br />
            {<br />
                <br />
                Validator.ValidateProperty(value, new ValidationContext(this, null, null) { MemberName="UserName"});<br />
                _UserName = value; <br />
            }<br />
        } <br />

<DataTemplate DataType="{x:Type vm:ClockViewModel}">
    <vw:DigitalClock/>
</DataTemplate>

ClockViewModel vm1 = new ClockViewModel();
tabItem1.Content = vm1;

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
using System.Windows.Media.Animation;
using System.Windows.Browser;


namespace K12
{
	
			public class YouTubePlayer : IDisposable
    {

        /// <summary>
        /// The default with of a player, if none is specified.
        /// </summary>
        public const int DefaultWidth = 425;

        /// <summary>
        /// The default height of a player, if none is specified.
        /// </summary>
        public const int DefaultHeight = 344;

        #region Private properties
        private string uniqueId = Guid.NewGuid().ToString();

        private double top;
        private double left;
        private double height = DefaultHeight;
        private double width = DefaultWidth;

        private string videoId;
        private bool isEmbeded;
        private HtmlElement div;
        #endregion

        /// <summary>
        /// Creates a player for the given video id. You must invoke Embed()
        /// later, to actually insert the video into the page.
        /// </summary>
        /// <param name="videoId"></param>
        public YouTubePlayer(string videoId)
        {
            this.videoId = videoId;
        }

        /// <summary>
        /// The absolute y position of this player.
        /// </summary>
        public double Top
        {
            get { return top; }
            set
            {
                top = value;

                if (isEmbeded)
                {
                    SetStyleProperty(DivId, "top", "\"" + (int)top + "px\"");
                }
            }
        }

        /// <summary>
        /// The absolute x position of this player.
        /// </summary>
        public double Left
        {
            get { return left; }
            set
            {
                left = value;

                if (isEmbeded)
                {
                    SetStyleProperty(DivId, "left", "\"" + (int)left + "px\"");
                }
            }
        }

        /// <summary>
        /// The height of this player.
        /// </summary>
        public double Height
        {
            get { return height; }
            set
            {
                height = value;

                if (isEmbeded)
                {
                    SetAllDivsProperty("height", "\"" + (int)height + "px\"");
                }
            }
        }

        /// <summary>
        /// The width of this player.
        /// </summary>
        public double Width
        {
            get { return width; }
            set
            {
                width = value;

                if (isEmbeded)
                {
                    SetAllDivsProperty("width", "\"" + (int)width + "px\"");
                }
            }
        }

        /// <summary>
        /// Allow fullscreen to be activated?
        /// </summary>
        public bool AllowFullScreen { get; set; }

        /// <summary>
        /// Embeds this player into the HTML page. Invoking this method many
        /// times has no effect. You must invoke Dipose() to remove the player
        /// form the HTML page.
        /// </summary>
        public void Embed()
        {
            if (isEmbeded) return;
            isEmbeded = true;

            div = HtmlPage.Document.CreateElement("div");
            div.SetAttribute("id", DivId);
            div.SetAttribute("style", "position: absolute; width:" + (int)Width + "px; height:" + (int)Height + "px; top: " + (int)Top + "px; left: " + (int)Left + "px; z-index:10");
            div.SetProperty("innerHTML",
                "<object width=\"" + (int)Width + "\" height=\"" + (int)Height + "\" id=\"" + ObjectId + "\">" +
                    "<param name=\"movie\" value=\"http://www.youtube.com/v/" + videoId + "&hl=en&fs=1\"></param>" +
                    "<param name=\"allowFullScreen\" value=\"" + AllowFullScreen + "\"></param>" +
                    "<embed id=\"" + EmbedId + "\" src=\"http://www.youtube.com/v/" + videoId + "&hl=en&fs=1\" type=\"application/x-shockwave-flash\" allowfullscreen=\"" + AllowFullScreen + "\" width=\"" + (int)Width + "\" height=\"" + (int)Height + "\"></embed>" +
                "</object>"
                );

            HtmlPage.Document.Body.AppendChild(div);
        }

        /// <summary>
        /// Removes this embedded player from the HTML page. Has no effect if this
        /// player was not embedded, or is already disposed.
        /// </summary>
        public void Dispose()
        {
            if (!isEmbeded) return;
            isEmbeded = false;

            HtmlPage.Document.Body.RemoveChild(div);
        }

        #region Implementation

        private string DivId { get { return "YouTubePlayer" + uniqueId; } }

        private string ObjectId { get { return "YouTubePlayer_Object_" + uniqueId; } }

        private string EmbedId { get { return "YouTubePlayer_Embed_" + uniqueId; } }

        private void SetAllDivsProperty(string property, object value)
        {
            SetProperty(DivId, property, value);
            SetProperty(ObjectId, property, value);
            SetProperty(EmbedId, property, value);
        }

        private void SetProperty(string divId, string property, object value)
        {
            HtmlPage.Window.Eval("document.getElementById(\"" + divId + "\")." + property + " = " + value + ";");
        }

        private void SetStyleProperty(string divId, string property, object value)
        {
            HtmlPage.Window.Eval("document.getElementById(\"" + divId + "\").style." + property + " = " + value + ";");
        }

        #endregion
    }
// Insert code required on object creation below this point.
	
	}

private void Page3_Loaded(object sender, System.Windows.RoutedEventArgs e)
       {

           YouTubePlayer player = new YouTubePlayer("5_a4zb9D4m4")
                  {
                   //Top = stalkpanel1.Marging.TOP+10,
                  // Left = stalkpanel1.Marging.Left+10,
                      Top = 100,
                      Left = 200,
                      Width = 400,
                      Height = 400
                 };


                player.Embed();

       }