设置实体类型中String类型的属性值为String.Empty

　　　　 /// <summary>
        ///  将String类型的属性值设置为String.Empty
        /// </summary>
        /// <typeparam name="T">强类型Entity</typeparam>
        /// <param name="result"></param>
        public static void DefaultStringProperty<T>(T result) where T : class
        {
            Type t = typeof(T);
            System.Reflection.PropertyInfo[] propertyInfos = t.GetProperties();
            foreach (PropertyInfo pi in propertyInfos)
            {
                if (pi.PropertyType.Equals(typeof(string)))
                {
                    object _origanlValue = pi.GetValue(result, null);
                    if (_origanlValue == null)
                    {
                        pi.SetValue(result, string.Empty, null);
                    }
                }
            }
        }