集合生成Json格式

         /// <summary>     
        /// dataTable转换成Json格式     
        /// </summary>     
        /// <param name="dt"></param>     
        /// <returns></returns>     
        public static string ToJson(DataTable dt)
        {
            if (dt != null && dt.Rows.Count > 0)
            {
                StringBuilder jsonBuilder = new StringBuilder();
                jsonBuilder.Append("{\"");
                jsonBuilder.Append("data");
                jsonBuilder.Append("\":[");
                for (int i = 0; i < dt.Rows.Count; i++)
                {
                    jsonBuilder.Append("{");
                    for (int j = 0; j < dt.Columns.Count; j++)
                    {
                        jsonBuilder.Append("\"");
                        jsonBuilder.Append(dt.Columns[j].ColumnName);
                        jsonBuilder.Append("\":\"");
                        jsonBuilder.Append(jsonStringFromat(dt.Rows[i][j].ToString()));
                        jsonBuilder.Append("\",");
                    }
                    jsonBuilder.Remove(jsonBuilder.Length - 1, 1);
                    jsonBuilder.Append("},");
                }
                jsonBuilder.Remove(jsonBuilder.Length - 1, 1);
                jsonBuilder.Append("]");
                jsonBuilder.Append("}");
                return jsonBuilder.ToString();
            }
            else
            {
                return "";
            }
        }

        /// <summary>
        /// Enumerable转成JSON
        /// </summary>
        /// <param name="list"></param>
        /// <returns></returns>
        public static string EnumerableToJson(IEnumerable list)
        {
            StringBuilder json = new StringBuilder();
            int i = 0;
            if (list != null)
            {
                json.Append("{\"data\":[");
                foreach (var item in list)
                {
                    json.Append("{");
                    PropertyInfo[] pi = item.GetType().GetProperties();
                    int j = 0;
                    foreach (var p in pi)
                    {
                        if (j < pi.Length - 1)
                        {
                            json.Append("\"" + p.Name.ToString() + "\":\"" + jsonStringFromat(p.GetValue(item, null).ToString()) + "\",");
                        }
                        else
                        {
                            json.Append("\"" + p.Name.ToString() + "\":\"" + jsonStringFromat(p.GetValue(item, null).ToString()) + "\"");
                        }
                        j++;
                    }
                    i++;
                    json.Append("},");
                }
                json.Remove(json.Length - 1, 1);
                json.Append("]}");
            }
            if (i != 0)
                return json.ToString();
            else
                return "";
        }