我怎样才能制作一个无限循环并暂停 5 秒

    string connectionstring = "server =SQLVS2\\SQLVS2;database=DDM;Persist Security Info=True;uid=ddmuser;password=User02+Ddm;";
    SqlConnection myConnection = new SqlConnection(connectionstring);
    SqlCommand myCommand = new SqlCommand("GetNullHash", myConnection);
    myCommand.CommandType = CommandType.StoredProcedure;
    myConnection.Open();
    SqlDataReader rdr = myCommand.ExecuteReader();

   while (rdr.Read())
    {
        string filename = @"\\" + rdr.GetString(3);
        filename = System.IO.Path.Combine(filename, rdr.GetString(2));
        filename = System.IO.Path.Combine(filename, rdr.GetString(1));
        computeHashh1 abc = new computeHashh1();
        Console.WriteLine(abc.computeHash(filename));          
        inserthash insert = new inserthash();
       insert.InsertHash(rdr.GetString(1), abc.computeHash(filename), rdr.GetStr(2),rdr.GetString(3));

    }

我怎样才能让这个循环每 5 秒运行一次，直到停止。

最简单的方法是：

while (true) {
    // code here
    Thread.Sleep(5000);
}

但是，为了更加稳健，我建议窗口服务 http://msdn.microsoft.com/en-us/library/zt39148a%28v=vs.80%29.aspx with a 适当的计时器 http://clifgriffin.com/2008/11/20/using-timers-in-a-c-windows-service/.