数据库导出数据

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Data.SqlClient;
 6 using System.IO;
 7
 8 namespace 数据库导出数据
 9 {
10     class Program
11     {
12         static void Main(string[] args)
13         {
14             string str = "Data Source =.; Initial Catalog = mysql; Integrated Security = True;";
15             string sql = "select * from users";
16
17             //Data Source=.;Initial Catalog=mysql;Integrated Security=True
18             //下面有4个using，streamwriter必须使用using！！
19             using (SqlConnection con = new SqlConnection(str))
20             {
21                 using (SqlCommand cmd = new SqlCommand(sql, con))
22                 {
23                     con.Open();
24                     using (SqlDataReader reader = cmd.ExecuteReader())
25                     {
26                         if (reader.HasRows)
27                         {
28                             using (StreamWriter sw = new StreamWriter("1.txt"))
29                             {
30                                 sw.WriteLine("{0},{1},{2}", reader.GetName(0), reader.GetName(1), reader.GetName(2));
31                                 while (reader.Read())
32                                 {
33                                     sw.WriteLine("{0},{1},{2}", reader[0], reader[1], reader[2]);
34                                 }
35                             }
36                         }
37                     }
38                 }
39             }
40             Console.WriteLine("导出成功！");
41             Console.ReadKey();
42         }
43     }
44 }