vs2005 xml 添加

using System.Xml;
using System.IO;

public partial class xmladd : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{

}
protected void btnSubmit_Click(object sender, EventArgs e)
{
XmlDocument xmldoc;
XmlNode root, stuNode;

string stuName = tbStuName.Text;
string phone = tbPhone.Text;
string qq = tbQQ.Text;
string email = tbEmail.Text;
string home = tbHome.Text;
string headImage = fileHeadImage.PostedFile.FileName;
string[] filename=headImage.Split('\\');
headImage=filename[filename.Length-1];
fileHeadImage.PostedFile.SaveAs(Server.MapPath(".")+"/"+headImage);
string work = tbWork.Text;

xmldoc = new XmlDocument();
xmldoc.Load(Server.MapPath("address.xml"));
root = xmldoc.DocumentElement;
XmlElement student = xmldoc.CreateElement("student");
XmlElement node1 = xmldoc.CreateElement("stuName");
node1.InnerText = stuName;
XmlElement node2 = xmldoc.CreateElement("phone");
node2.InnerText = phone;
XmlElement node3 = xmldoc.CreateElement("qq");
node3.InnerText = qq;
XmlElement node4 = xmldoc.CreateElement("email");
node4.InnerText = email;
XmlElement node5 = xmldoc.CreateElement("home");
node5.InnerText = home;
XmlElement node6 = xmldoc.CreateElement("headImage");
node6.InnerText = headImage;
XmlElement node7 = xmldoc.CreateElement("work");
node7.InnerText = work;