C#把list转化为Datatable

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使用linq的时候,经常需要 select new{ ...不固定的字段... }  ,如何读取这些字段的单个值?通常两种做法:1)object对象反射是可以做的  2)在反射的基础上,转化为datatable 也可以

如下实例:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using ConsoleApplication1;
using System.Data;
using System.Collections;
using System.Reflection;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args) 
        {

            /*创建数据源*/
            List<myclass> l = new List<myclass>();
            for (int i = 0; i < 10; i++)
            {
                myclass mc = new myclass();
                mc.age = i;
                mc.name = "myname" + i;
                l.Add(mc);
            }

            /*创建datatable*/
            DataTable dt = new DataTable();

            /*返回一个有任意字段的 List<Object>对象,   select new 中的namefull就是自己随意添加的字段*/
            List<Object> rs = (from r in l select new { name = r.name, namefull = r.name + r.age, age = r.age }).ToList<Object>();

            /*把List<Object>对象转化为Datatable对象*/
            dt = ToDataTableTow(rs);

            /*读取Datatable对象*/
            foreach (DataRow dr in dt.Rows)
            {
                /*按照拼接的字段名称 读取内容*/
                Console.WriteLine(dr["name"].ToString() +"-----------------"+ dr["namefull"].ToString());
            }
            Console.Read();
        }



        /// <summary>  
        /// 将集合类转换成DataTable  
        /// </summary>  
        /// <param name="list">集合</param>  
        /// <returns></returns>  
        public static DataTable ToDataTableTow(IList list)
        {
            DataTable result = new DataTable();
            if (list.Count > 0)
            {
                PropertyInfo[] propertys = list[0].GetType().GetProperties();

                foreach (PropertyInfo pi in propertys)
                {
                    result.Columns.Add(pi.Name, pi.PropertyType);
                }
                for (int i = 0; i < list.Count; i++)
                {
                    ArrayList tempList = new ArrayList();
                    foreach (PropertyInfo pi in propertys)
                    {
                        object obj = pi.GetValue(list[i], null);
                        tempList.Add(obj);
                    }
                    object[] array = tempList.ToArray();
                    result.LoadDataRow(array, true);
                }
            }
            return result;
        }
    }

    public class myclass
    {

        public string name;
        public int age;
    }
}

结果: