private void button1_Click(object sender, EventArgs e)              {                  if (openFileDialog1.ShowDialog() == DialogResult.OK)        {               using (FileStream fs = File.OpenRead(openFileDialog1.FileName))       {                    using (StreamReader sr = new StreamReader(fs, System.Text.Encoding.GetEncoding("GB2312")))         {      //<span style="color:#3333ff;">必需设置字符编码System.Text.Encoding.GetEncoding("GB2312")，      不然string name = arr[0]中的name就是乱码</span>                           using (SqlConnection conn = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename='|DataDirectory|\dd.mdf';      Integrated Security=True;User Instance=True"))        {      //<span style="color:#3333ff;">DataDirectory指的是数据库的绝对路径，winForm里面的Program.cs必需添加代码，否则是.NET是找到的数据库是有问题的，实在不懂可以去博客园自己去看看why</span>                                  conn.Open();                          using (SqlCommand cmd = conn.CreateCommand())            {                               cmd.CommandText = "insert into T_Persons values(@Name,@Age)";      string line = "";            while ((line = sr.ReadLine()) != null)        {                      string[] arr = line.Split('|');            string name = arr[0];                 int age = Convert.ToInt32(arr[1]);       cmd.Parameters.Clear();//别忘了               cmd.Parameters.Add(new SqlParameter("Name", name));       cmd.Parameters.Add(new SqlParameter("Age", age));        cmd.ExecuteNonQuery();             }                          }                          }                         }                     }                     MessageBox.Show("txt导入数据库成功!");         }                     }              private void button2_Click(object sender, EventArgs e)          {                  if (saveFileDialog1.ShowDialog() == DialogResult.OK)           {                       using (FileStream fs = File.OpenWrite(saveFileDialog1.FileName))       {                        using (StreamWriter sw = new StreamWriter(fs, System.Text.Encoding.GetEncoding("GB2312")))          {                           using (SqlConnection conn = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename='|DataDirectory|\dd.mdf';Integrated Security=True;User Instance=True"))                               {                               conn.Open();             using (SqlCommand cmd = conn.CreateCommand())           {                                   cmd.CommandText = "select * from T_Persons";         using (SqlDataReader sdr = cmd.ExecuteReader())          {                                                  while (sdr.Read())                    {                                    string name = sdr.GetString(sdr.GetOrdinal("Name"));      int age = sdr.GetInt32(sdr.GetOrdinal("Age"));        string line =name+"|"+age;                           sw.WriteLine(line);                                sw.Flush();                             }                                           }                            }                       }                        }                   }                MessageBox.Show("导出数据到txt成功！");        }              }      </span> 

static void Main()         {           string dataDir = AppDomain.CurrentDomain.BaseDirectory;       if (dataDir.EndsWith(@"\bin\Debug\") || dataDir.EndsWith(@"\bin\Release\"))   {                 dataDir = System.IO.Directory.GetParent(dataDir).Parent.Parent.FullName;   AppDomain.CurrentDomain.SetData("DataDirectory", dataDir);     }                Application.EnableVisualStyles();  Application.SetCompatibleTextRenderingDefault(false);     Application.Run(new Form1());     }