ASP.Net Website root folder

To access to the root folder in website :  Server.MapPath("~/")

This sample demonstrates to create or to open a file in the root folder of website, then writes test text into it.

using System;
using System.IO;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        string root = Server.MapPath("~/");
        string path = root + "testselim.txt";

        using (FileStream fs = new FileStream(path, FileMode.OpenOrCreate))
        {
            using (StreamWriter sw = new StreamWriter(fs))
            {
                sw.WriteLine("Test Text");
                sw.Close();
            }
            fs.Close();
        }
    }
}