C# DataTable转换成实体列表 与 实体列表转换成DataTable

Posted 2020-08-27

/// <summary>
        /// DataTable转换成实体列表
        /// </summary>
        /// <typeparam name="T">实体 T </typeparam>
        /// <param name="table">datatable</param>
        /// <returns></returns>
        public static IList<T> DataTableToList<T>(DataTable table)
            where T : class
        {
            if (!IsHaveRows(table))
                return new List<T>();

            IList<T> list = new List<T>();
            T model = default(T);
            foreach (DataRow dr in table.Rows)
            {
                model = Activator.CreateInstance<T>();

                foreach (DataColumn dc in dr.Table.Columns)
                {
                    object drValue = dr[dc.ColumnName];
                    PropertyInfo pi = model.GetType().GetProperty(dc.ColumnName);

                    if (pi != null && pi.CanWrite && (drValue != null && !Convert.IsDBNull(drValue)))
                    {
                        pi.SetValue(model, drValue, null);
                    }
                }

                list.Add(model);
            }
            return list;
        }


        /// <summary>
        /// 实体列表转换成DataTable
        /// </summary>
        /// <typeparam name="T">实体</typeparam>
        /// <param name="list"> 实体列表</param>
        /// <returns></returns>
        public static DataTable ListToDataTable<T>(IList<T> list)
            where T : class
        {
            if (list == null || list.Count <= 0)
            {
                return null;
            }
            DataTable dt = new DataTable(typeof(T).Name);
            DataColumn column;
            DataRow row;

            PropertyInfo[] myPropertyInfo = typeof(T).GetProperties(BindingFlags.Public | BindingFlags.Instance);

            int length = myPropertyInfo.Length;
            bool createColumn = true;

            foreach (T t in list)
            {
                if (t == null)
                {
                    continue;
                }

                row = dt.NewRow();
                for (int i = 0; i < length; i++)
                {
                    PropertyInfo pi = myPropertyInfo[i];
                    string name = pi.Name;
                    if (createColumn)
                    {
                        column = new DataColumn(name, pi.PropertyType);
                        dt.Columns.Add(column);
                    }

                    row[name] = pi.GetValue(t, null);
                }

                if (createColumn)
                {
                    createColumn = false;
                }

                dt.Rows.Add(row);
            }
            return dt;

        }