DataTable和实体集合互转(C#)

 /// <summary>
        /// DataTable转成List
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="dt"></param>
        /// <returns></returns>
        public static List<T> GetTableToList<T>(this DataTable dt)
        {
            var list = new List<T>();
            var plist = new List<PropertyInfo>(typeof(T).GetProperties());
            foreach (DataRow item in dt.Rows)
            {
                T s = Activator.CreateInstance<T>();
                for (int i = 0; i < dt.Columns.Count; i++)
                {
                    PropertyInfo info = plist.Find(p => p.Name == dt.Columns[i].ColumnName);
                    if (info != null)
                    {
                        try
                        {
                            if (!Convert.IsDBNull(item[i]))
                            {
                                object v = null;
                                if (info.PropertyType.ToString().Contains("System.Nullable"))
                                {
                                    v = Convert.ChangeType(item[i], Nullable.GetUnderlyingType(info.PropertyType));
                                }
                                else
                                {
                                    v = Convert.ChangeType(item[i], info.PropertyType);
                                }
                                info.SetValue(s, v, null);
                            }
                        }
                        catch (Exception ex)
                        {
                            throw new Exception("字段[" + info.Name + "]转换出错," + ex.Message);
                        }
                    }
                }
                list.Add(s);
            }
            return list;
        }


        /// <summary>
        /// List集合转DataTable
        /// </summary>
        /// <typeparam name="T">实体类型</typeparam>
        /// <param name="list">传入集合</param>
        /// <returns>返回datatable结果</returns>
        public static DataTable GetListToTable<T>(List<T> list)
        {
            Type tp = typeof(T);
            PropertyInfo[] proInfos = tp.GetProperties();
            DataTable dt = new DataTable();
            foreach (var item in proInfos)
            {
                dt.Columns.Add(item.Name, item.PropertyType); //添加列名及对应类型
            }
            foreach (var item in list)
            {
                DataRow dr = dt.NewRow();
                foreach (var proInfo in proInfos)
                {
                    object obj = proInfo.GetValue(item);
                    if (obj == null)
                    {
                        continue;
                    }
                    dr[proInfo.Name] = obj;
                }
                dt.Rows.Add(dr);
            }
            return dt;
        }

 

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