cmb省cmb市

 

       private void Form1_Load(object sender, EventArgs e)<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

        {

            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);

            }

 

            using (SqlConnection conn = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database1.mdf;Integrated Security=True;User Instance=True"))

            {

                conn.Open();

               using(SqlCommand cmd = conn.CreateCommand())

               {

                   cmd.CommandText = "select * from promary";

                   using (SqlDataReader reader = cmd.ExecuteReader())

                   {

                       while (reader.Read())

                       {

                           string proname = reader.GetString(reader.GetOrdinal("proName"));

 

                           cmb省.Items.Add(proname);

 

                       }

                    }

               }

            }

 

 

        }

 

        private void cmb省_SelectedIndexChanged(object sender, EventArgs e)

        {

            cmb市.Items.Clear();

            cmb市.Text = "";

            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);

            }

 

            using (SqlConnection conn = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database1.mdf;Integrated Security=True;User Instance=True"))

            {

                conn.Open();

                using (SqlCommand cmd = conn.CreateCommand())

                {

                      //查询省名对应的省ID，再从省ID获得市名

                    cmd.CommandText = "select * from city where proID=(select ProID from promary where proName=@ProName)";

                    cmd.Parameters.Add(new SqlParameter("proName", cmb省.Text));

                    using (SqlDataReader reader = cmd.ExecuteReader())

                    {

                        while(reader.Read())

                        {

                            string cityname=reader.GetString(reader.GetOrdinal("cityName"));

                            cmb市.Items.Add(cityname);

                        }

                    }

                }

            }

        }

private void btnDaoru_Click(object sender, EventArgs e)   //数据导入<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

        {   //初始化代码

            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);

            }

 

            if (odfImport.ShowDialog() != DialogResult.OK)

            {

                return; //判断是否点击ok

            }

            using (FileStream filestream = File.OpenRead(odfImport.FileName))

            {  //打开读文件流

                using (StreamReader streamReader = new StreamReader(filestream))

                {  //打开读字符流

 

 

                    using (SqlConnection conn = new SqlConnection((@"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database1.mdf;Integrated Security=True;User Instance=True

")))

                    {  //连接并打开数据库

                        conn.Open();

 

 

                        using (SqlCommand cmd = conn.CreateCommand())

                        { //与数据库交谈

                            cmd.CommandText = "Insert into T_person(Name,Age) values(@Name,@Age)";

                            string line = null; ;

                            while ((line = streamReader.ReadLine()) != null)

                            {

                                string[] strs = line.Split('|');

                                string name = strs[0];

                                int age = Convert.ToInt32(strs[1]);

                                cmd.Parameters.Clear();

                                cmd.Parameters.Add(new SqlParameter("Name", name));

                                cmd.Parameters.Add(new SqlParameter("Age", age));

                                cmd.ExecuteNonQuery(); //执行查询

                            }

                        }

                    }

 

                }

            }

            MessageBox.Show("导入成功!");

        }

数据的导出

        private void btnDaochu_Click(object sender, EventArgs e)    //数据导出<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

        {

            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);

            }

 

            if (saveFileDialog1.ShowDialog() != DialogResult.OK)

            {

                return; //判断是否点击ok

            }

            using (FileStream filestream = File.OpenWrite(saveFileDialog1.FileName))

            {  //打开写文件流

                using(StreamWriter streamwriter=new StreamWriter(filestream))

                { //打开写字符流

                    using (SqlConnection conn = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database1.mdf;Integrated Security=True;User Instance=True"))

                    { //连接数据库并打开

                        conn.Open();

                        using(SqlCommand cmd= conn.CreateCommand())

                        { //与数据库交谈

                            cmd.CommandText = "select Name,Age from  T_person";

 

                            using (SqlDataReader reader = cmd.ExecuteReader())

                            { //执行多行查询

                              while(reader.Read())

                              {

                                  string Name = reader.GetString(reader.GetOrdinal("Name"));

                                  string Age = Convert.ToString(reader.GetInt32(reader.GetOrdinal("Age")));

                                  string line = Name + '|' + Age;

                                  streamwriter.WriteLine(line);

                              }

 

                            }

 

                        }

 

                    }

                }

 

            }

 

            MessageBox.Show("导出成功!");

        }