Linq to xml

Hi this is for binding xml file to a gridview.
i used this code in load event.it is working.
i want to write this in a function.
ie if i enter name in a textbox and enter the button the corresponding city and age should be displayed.

XDocument xmlDoc = XDocument.Load(Server.MapPath("People.xml"));
            var persons = from person in xmlDoc.Descendants("Person")
                          select new
                          {
                              Name = person.Element("Name").Value,
                              City = person.Element("City").Value,
                              Age = person.Element("Age").Value,
                          };
            
            GridView1.DataSource = persons;
            GridView1.DataBind();

i tried this type

public string bind(string ename)
{

 XDocument xmlDoc = XDocument.Load(Server.MapPath("People.xml"));
            var persons = from person in xmlDoc.Descendants("Person") where name==ename
                          select new
                          {
                              Name = person.Element("Name").Value,
                              City = person.Element("City").Value,
                              Age = person.Element("Age").Value,
                          };
return persons;

}

how it possible

Regards
K L BAIJU