数据库文件导出

 //string[] content=new string[100];//数组一定要new出来，切记，切记！！！
        List<string> content=new List<string>();
        private void button2_Click(object sender, RoutedEventArgs e)
        {
            using (SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["connStr"].ConnectionString))
            {
                conn.Open();
                using(SqlCommand cmd=new SqlCommand())
                {
                    cmd.CommandText="select Name,Password from T_Login";
                    cmd.Connection=conn;
                    SqlDataAdapter adapter=new SqlDataAdapter(cmd);
                    DataSet ds=new DataSet();
                    adapter.Fill(ds);
                    DataRowCollection rows= ds.Tables[0].Rows;
                    foreach (DataRow row in rows)
                    {
                        //string c = row[0].ToString() + row[1].ToString();
                        content.Add((string)row[0]+"  "+(string)row[1]);
                    }
                }
                File.WriteAllLines("C:/2.txt", content);
            }
            MessageBox.Show("导出完毕");
        }