Please assist.

New to C#.  This below code is in a book it was used in VS 2005.  I'm using
VS 2008.

On this line:
 using (System.IO.StreamWriter writer = new System.IO.StreamWriter(Filepath))
Error Msg:
The name 'Filepath' does not exist in the current context

Code:

using System;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Xml.Linq;

[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
// To allow this Web Service to be called from script, using ASP.NET AJAX,
uncomment the following line.
// [System.Web.Script.Services.ScriptService]
public class Service : System.Web.Services.WebService
{
   public Service () {

       //Uncomment the following line if using designed components
       //InitializeComponent();
   }

   [WebMethod]
   public string HelloWorld() {
       return "Hello World";
   }

   private string FilePath = System.IO.Path.Combine(
       Environment.GetEnvironmentVariable("Temp"),
       "SavedItems.txt");
   [WebMethod]
   public string[] GetSavedItems()
   {
       using (System.IO.StreamReader reader =
           new System.IO.StreamReader(FilePath))
       {
           string filedata = reader.ReadToEnd();
           return filedata.Split('\n');
       }

   }
   [WebMethod]

   public void SaveItem(string item)
   {
       SaveItems(new string[] {item});
   }
   [WebMethod]

   public void SaveItems(string[] items)
   {
       using (System.IO.StreamWriter writer = new
System.IO.StreamWriter(Filepath))
   {
   foreach (string item in items)
       {
   writer.WriteLine(item);
       }
   }
}

}

Thanks