List转Datable(需区分对象充当List成员和数组充当List成员两种情况)

对象充当List成员时:

/// <summary>

        /// 将泛类型集合List类转换成DataTable

        /// </summary>

        /// <param name="list">泛类型集合</param>

        /// <returns></returns>

        public static DataTable ListToDataTable<T>(List<T> entitys)

        {

            //检查实体集合不能为空

            if (entitys == null || entitys.Count < 1)

            {

                throw new Exception("需转换的集合为空");

            }

            //取出第一个实体的所有Propertie

            Type entityType = entitys[0].GetType();

            PropertyInfo[] entityProperties = entityType.GetProperties();

 

            //生成DataTable的structure

            //生产代码中,应将生成的DataTable结构Cache起来,此处略

            DataTable dt = new DataTable();

            for (int i = 0; i < entityProperties.Length; i++)

            {

                //dt.Columns.Add(entityProperties[i].Name, entityProperties[i].PropertyType);

                dt.Columns.Add(entityProperties[i].Name);

            }

            //将所有entity添加到DataTable中

            foreach (object entity in entitys)

            {

                //检查所有的的实体都为同一类型

                if (entity.GetType() != entityType)

                {

                    throw new Exception("要转换的集合元素类型不一致");

                }

                object[] entityValues = new object[entityProperties.Length];

                for (int i = 0; i < entityProperties.Length; i++)

                {

                    entityValues[i] = entityProperties[i].GetValue(entity, null);

                }

                dt.Rows.Add(entityValues);

            }

            return dt;

        }

 

数组充当List成员时:

public static DataTable ListArrayToDataTable(List<string[]> entitys, string[] colname = null)

        {

            //检查实体集合不能为空

            if (entitys == null || entitys.Count < 1)

            {

                throw new Exception("需转换的集合为空");

            }

 

            DataTable dt = new DataTable();

 

            if (colname != null)

            {

                if (colname.Length != entitys[0].Length)

                    throw new Exception("名称数组与成员数组维度不一致");

 

                foreach (string nm in colname)

                    dt.Columns.Add(nm, typeof(string));

            }

            else

            {

                foreach (string nm in entitys[0])

                    dt.Columns.Add("", typeof(string));

            }

 

            //将所有entity添加到DataTable中

            foreach (string[] entity in entitys)

            {

                if (entity.Length != entitys[0].Length)

                {

                    throw new Exception("数组维度不一致");

                }

 

 

                dt.Rows.Add(entity);

            }

            return dt;

        }

 

原文地址:https://www.cnblogs.com/mol1995/p/6570915.html