JSONHelper

/// <summary>

        /// DataTable 转换为JSON 字符串

        /// </summary>

        /// <param name="dt"></param>

        /// <returns></returns>

        public static string ToJson(this DataTable dt)

        {

            JavaScriptSerializer javaScriptSerializer = new JavaScriptSerializer();

            javaScriptSerializer.MaxJsonLength = Int32.MaxValue; //取得最大数值

            ArrayList arrayList = new ArrayList();

            foreach (DataRow dataRow in dt.Rows)

            {

                Dictionary<string, object> dictionary = new Dictionary<string, object>();  //实例化一个参数集合

                foreach (DataColumn dataColumn in dt.Columns)

                {

                    dictionary.Add(dataColumn.ColumnName, dataRow[dataColumn.ColumnName].ToStr());

                }

                arrayList.Add(dictionary); //ArrayList集合中添加键值

            }



            return javaScriptSerializer.Serialize(arrayList);  //返回一个json字符串

        }

        #endregion



        #region JSON 字符串 转换为 DataTable数据集合

        /// <summary>

        /// JSON 字符串 转换为 DataTable数据集合

        /// </summary>

        /// <param name="json"></param>

        /// <returns></returns>

        public static DataTable ToDataTable(this string json)

        {

            DataTable dataTable = new DataTable();  //实例化

            DataTable result;

            try

            {

                JavaScriptSerializer javaScriptSerializer = new JavaScriptSerializer();

                javaScriptSerializer.MaxJsonLength = Int32.MaxValue; //取得最大数值

                ArrayList arrayList = javaScriptSerializer.Deserialize<ArrayList>(json);

                if (arrayList.Count > 0)

                {

                    foreach (Dictionary<string, object> dictionary in arrayList)

                    {

                        if (dictionary.Keys.Count<string>() == 0)

                        {

                            result = dataTable;

                            return result;

                        }

                        if (dataTable.Columns.Count == 0)

                        {

                            foreach (string current in dictionary.Keys)

                            {

                                dataTable.Columns.Add(current, dictionary[current].GetType());

                            }

                        }

                        DataRow dataRow = dataTable.NewRow();

                        foreach (string current in dictionary.Keys)

                        {

                            dataRow[current] = dictionary[current];

                        }



                        dataTable.Rows.Add(dataRow); //循环添加行到DataTable中

                    }

                }

            }

            catch

            {

            }

            result = dataTable;

            return result;

        }

        #endregion



        #region 转换为string字符串类型

        /// <summary>

        ///  转换为string字符串类型

        /// </summary>

        /// <param name="s">获取需要转换的值</param>

        /// <param name="format">需要格式化的位数</param>

        /// <returns>返回一个新的字符串</returns>

        public static string ToStr(this object s, string format = "")

        {

            string result = "";

            try

            {

                if (format == "")

                {

                    result = s.ToString();

                }

                else

                {

                    result = string.Format("{0:" + format + "}", s);

                }

            }

            catch

            {

            }

            return result;

        }