gistfile1.cs

[Serializable]
    public static class ForceToken
    {
        private static DateTime _sessionDate = DateTime.Now;
        private static string _sessionId = string.Empty;
        public static string SessionId
        {
            get { return GetSession(); }
        }
        private static string GetSession()
        {
            DateTime now = DateTime.Now;
            TimeSpan diff = now.Subtract(_sessionDate);
            if (_sessionId == string.Empty || (diff.Minutes > 60))
            {
                //TODO lock object during update
                //refresh token
                System.Diagnostics.EventLog.WriteEntry("Utilities", "Salesforce.com Session Refresh");
                string uname = "<sf account>";
                string password = "<sf password>";
                string securityToken = "<sf token>";
                SFSvcRef.SforceService proxy = new SFSvcRef.SforceService();
                proxy.Url = "https://www.salesforce.com/services/Soap/c/16.0";
                SFSvcRef.LoginResult result = proxy.login(uname, password + securityToken);
                _sessionId = result.sessionId;
            }
            return _sessionId;
        }
    }