DataTable 对象 转换为Json 字符串

 
/// <summary>
        /// DataTable 对象 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].ToString().Trim());
                }
                arrayList.Add(dictionary); //ArrayList集合中添加键值
            }

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