C#中从数据库导出至txt

用'|'隔开

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Data.SqlClient;

namespace 导出数据库表至txt
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (sfd.ShowDialog() == DialogResult.OK)
            {
                using (FileStream fstream = File.OpenWrite(sfd.FileName))
                {
                    StreamWriter sw = new StreamWriter(fstream, System.Text.Encoding.GetEncoding("GB2312"));
                    
                    using (SqlConnection conn = new SqlConnection("server=.;database=test;user id=sa;password=123456"))
                    {
                        conn.Open();
                     
                        using (SqlCommand cmd = conn.CreateCommand())
                        {
                            cmd.CommandText = "select * from T_persons";
                            using (SqlDataReader reader=cmd.ExecuteReader())
                            {
                                while (reader.Read())
                                {
                                    string name = reader.GetString(reader.GetOrdinal("name"));
                                    int age = reader.GetInt32(reader.GetOrdinal("age"));
                                    sw.WriteLine(name + "|" + age);

                                }
                                sw.Flush();
                            }

                        }
                    }
                    MessageBox.Show("数据导出成功！");
                }
            }
        }

      
    }
}