Parse a string to Enum

 if (Enum.IsDefined(typeof(EnStatus), this.HttpContext.Request.Form["payment_status"]))             {                 result.status = (EnStatus)Enum.Parse(typeof                  (EnStatus), this.HttpContext.Request.Form["payment_status"]);             }

http://blogs.msdn.com/b/tims/archive/2004/04/02/106310.aspx