Save picture as XML and retrieve pic from xml file

<form id="form1" runat="server">
<asp:FileUpload ID="FileUpload1" runat="server" />
<asp:Button ID="Button1" runat="server" Text="Button" onclick="Button1_Click" />
<asp:Button ID="Button2" runat="server" onclick="Button2_Click" Text="Button" />
</form> //Code

using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.IO;
using System.Xml;
using System.Xml.Serialization;
using System.Text;
public partial class Pages_PageTest : Page
{
protected void Page_Load(object sender, EventArgs e)
{

}
protected void Button1_Click(object sender, EventArgs e)
{
Stream F_Stream = this.FileUpload1.PostedFile.InputStream;
BinaryReader br = new BinaryReader(F_Stream,System.Text.Encoding.Default);
byte[] data = new byte[F_Stream.Length];
br.Read(data, 0, data.Length);
StringBuilder strb = new StringBuilder();
strb.Append(Convert.ToBase64String(data));
Pic pbj = new Pic();
pbj.s_pid = strb.ToString();
pbj.id = 3;
FileStream fs = null;
try
{
XmlSerializer xs = new XmlSerializer(typeof(Pic));
fs = new FileStream(Server.MapPath("~/a.xml"), FileMode.Create, FileAccess.Write);
xs.Serialize(fs, pbj);

fs.Close();
}
catch (Exception ex)
{
if (fs != null)
fs.Close();
throw new Exception("Xml serialization failed!");
}

}
protected void Button2_Click(object sender, EventArgs e)
{

FileStream fs = null;
try
{

XmlSerializer xs = new XmlSerializer(typeof(Pic));
fs = new FileStream(Server.MapPath("~/a.xml"), FileMode.Open, FileAccess.ReadWrite);
Pic obj = xs.Deserialize(fs) as Pic;

byte[] data= Convert.FromBase64String(obj.s_pid);
Response.BinaryWrite(data);
Response.End();
fs.Close();
}
catch (Exception ex)
{
if (fs != null)
fs.Close();
throw new Exception("Xml serialization failed!");
}
}
}
public class Pic
{
public string s_pid;
public int id;
}