数据库导出数据

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient;
using System.IO;

namespace 数据库导出数据
{
    class Program
    {
        static void Main(string[] args)
        {
            string str = "Data Source =.; Initial Catalog = mysql; Integrated Security = True;";
            string sql = "select * from users";

            //Data Source=.;Initial Catalog=mysql;Integrated Security=True
            //下面有4个using，streamwriter必须使用using！！
            using (SqlConnection con = new SqlConnection(str))
            {
                using (SqlCommand cmd = new SqlCommand(sql, con))
                {
                    con.Open();
                    using (SqlDataReader reader = cmd.ExecuteReader())
                    {
                        if (reader.HasRows)
                        {
                            using (StreamWriter sw = new StreamWriter("1.txt"))
                            {
                                sw.WriteLine("{0},{1},{2}", reader.GetName(0), reader.GetName(1), reader.GetName(2));
                                while (reader.Read())
                                {
                                    sw.WriteLine("{0},{1},{2}", reader[0], reader[1], reader[2]);
                                }
                            }
                        }
                    }
                }
            }
            Console.WriteLine("导出成功！");
            Console.ReadKey();
        }
    }
}