C#DataTable与List/Json/Dictionary互相转换

之前写过DataTable转List和List转DataTable的文章，今天在项目中偶然发现有Json转DataTable的公共方法，话不多说先写一篇博客备份一下，感觉以后要用到的地方还是蛮多的。

核心代码:

#region  数据表DataTable 转键值对集合 List
        /// <summary>
        /// 数据表DataTable 转键值对集合 List
        /// 把DataTable转成 List集合, 存每一行
        /// 集合中放的是键值对字典,存每一列
        /// </summary>
        /// <param name="dt">数据表</param>
        /// <returns>哈希表数组</returns>
        public static List<Dictionary<string, object>> DataTableToList(DataTable dt)
        {
            List<Dictionary<string, object>> list
                 = new List<Dictionary<string, object>>();

            foreach (DataRow dr in dt.Rows)
            {
                Dictionary<string, object> dic = new Dictionary<string, object>();
                foreach (DataColumn dc in dt.Columns)
                {
                    dic.Add(dc.ColumnName, dr[dc.ColumnName]);
                }
                list.Add(dic);
            }
            return list;
        }
        #endregion

        #region 数据集转键值对数组字典

        /// <summary>
        /// 数据集转键值对数组字典
        /// </summary>
        /// <param name="dataSet">数据集</param>
        /// <returns>键值对数组字典</returns>
        public static Dictionary<string, List<Dictionary<string, object>>> DataSetToDic(DataSet ds)
        {
            Dictionary<string, List<Dictionary<string, object>>> result = new Dictionary<string, List<Dictionary<string, object>>>();

            foreach (DataTable dt in ds.Tables)
                result.Add(dt.TableName, DataTableToList(dt));

            return result;
        }
        #endregion

        #region 数据表Tables 转JSON
        /// <summary>
        /// 数据表转Tables JSON
        /// </summary>
        /// <param name="dataTable">数据表</param>
        /// <returns>JSON字符串</returns>
        public static string DataTableToJSON(DataTable dt)
        {
            return JsonHelper.ObjectToJSON(DataTableToList(dt));
        }
        #endregion

        #region 将datatable转换为json
        /// <summary>
        /// 将datatable转换为json
        /// </summary>
        /// <param name="dtb">Dt</param>
        /// <returns>JSON字符串</returns>
        public static string Dtb2Json(DataTable dtb)
        {
            //JavaScriptSerializer jss = new JavaScriptSerializer();

            System.Collections.ArrayList dic = new System.Collections.ArrayList();

            foreach (DataRow dr in dtb.Rows)
            {
                System.Collections.Generic.Dictionary<string, object> drow = new System.Collections.Generic.Dictionary<string, object>();

                foreach (DataColumn dc in dtb.Columns)
                {
                    drow.Add(dc.ColumnName, dr[dc.ColumnName]);
                }

                dic.Add(drow);
            }

            return null;
        }
        #endregion

        #region 将Dictionary转换为数据表数据 Tables
        public static DataTable DictToDataTable(Dictionary<string, object> dict)
        {
            DataTable dt = new DataTable();

            //dt.Columns.Add("ID", typeof(Guid));
            //dt.Columns.Add("REMARKS", typeof(string));

            foreach (var colName in dict.Keys)
            {
                dt.Columns.Add(colName, typeof(string));
            }
            DataRow dr = dt.NewRow();
            foreach (KeyValuePair<string, object> item in dict)
            {
                dr[item.Key] = item.Value;
            }
            dt.Rows.Add(dr);
            return dt;
        }
        #endregion

        #region 将List转换为数据表数据 Tables
        /// <summary>
        /// List转DataTable
        /// </summary>
        public static DataTable ListToDataTable<T>(List<T> list)
        {
            if (list == null || list.Count == 0)
            {
                return new DataTable();
            }

            //获取T下所有的属性
            Type entityType = list[0].GetType();
            PropertyInfo[] entityProperties = entityType.GetProperties();

            DataTable dt = new DataTable("data");

            for (int i = 0; i < entityProperties.Length; i++)
            {
                dt.Columns.Add(entityProperties[i].Name);
            }

            foreach (var item in list)
            {
                if (item.GetType() != entityType)
                {
                    throw new Exception("要转换集合元素类型不一致！");
                }
                //创建一个用于放所有属性值的数组
                object[] entityValues = new object[entityProperties.Length];
                for (int i = 0; i < entityProperties.Length; i++)
                {
                    entityValues[i] = entityProperties[i].GetValue(item, null);
                }

                dt.Rows.Add(entityValues);
            }
            return dt;
        }
        #endregion

        #region  Json 字符串 转换为 DataTable数据集合  简要版，正在使用中
        /// <summary>
        /// Json 字符串 转换为 DataTable数据集合  简要版，正在使用中
        /// </summary>
        /// <param name="json"></param>
        /// <returns></returns>
        ///
        //格式;
        //[{"mac":"20:f1:7c:c5:cd:80","rssi":"-86","ch":"9"},{"mac":"20:f1:7c:c5:cd:85","rssi":"-91","ch":"9"}]
        public static DataTable ToDataTableTwo(string json)
        {
            DataTable dataTable = new DataTable();  //实例化
            DataTable result;
            try
            {
                List<Dictionary<string, object>> arrayList = JsonHelper.JSONToObject<List<Dictionary<string, object>>>(json);

                if (arrayList != null && arrayList.Count > 0)
                {
                    foreach (Dictionary<string, object> dictionary in arrayList)
                    {
                        if (dictionary.Keys.Count == 0)
                        {
                            result = dataTable;
                            return result;
                        }

                        //Columns
                        if (dataTable.Columns.Count == 0)
                        {
                            foreach (var current in dictionary)
                            {
                                if (current.Value != null)
                                {
                                    dataTable.Columns.Add(current.Key, current.Value.GetType());
                                }
                                else
                                {
                                    dataTable.Columns.Add(current.Key);
                                }
                            }
                        }

                        //Rows
                        DataRow dataRow = dataTable.NewRow();

                        foreach (string current in dictionary.Keys)
                        {
                            if (dictionary[current] != null)
                            {
                                dataRow[current] = dictionary[current];
                            }
                        }

                        dataTable.Rows.Add(dataRow); //循环添加行到DataTable中
                    }
                }
            }
            catch (Exception ex)
            {
                throw ex;
            }

            result = dataTable;
            return result;
        }
        #endregion

常见的基本都有了，如果不可用可以自己再二次开发一下，有些方法我也没怎么用过，不知道是不是还能使用，有问题可以在文章下方留言，看到我会第一时间回复。