（分享)(新手项目）ADO.NET省市选择代码

IT弄你 2013-03-17 08:50:04

效果图

代码

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Data.SqlClient;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Windows.Forms;



namespace 省市选择

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }



        private void Form1_Load(object sender, EventArgs e)

        {



            using (SqlConnection coon = new SqlConnection(@"Data Source=(LocalDB)\v11.0;AttachDbFilename=E:\新建文件夹\exam\test9\SQLtest9.mdf;Integrated Security=True"))

            {

                cmbshi.Items.Clear();

                coon.Open();

                using(SqlCommand cmd=coon.CreateCommand())

                {

                    cmd.CommandText = "select * from shen;";

                    using(SqlDataReader reader=cmd.ExecuteReader())

                    {

                        while (reader.Read())

                        {

                            ids id = new ids();

                            id.id= reader.GetInt32(reader.GetOrdinal("id"));

                            id.shen=reader.GetString(reader.GetOrdinal("省"));

                            cmbshen.Items.Add(id);

                        }



                    }

                }

            }

        }



        private void cmbshen_SelectedIndexChanged(object sender, EventArgs e)

        {

            txtqh.Clear();

            ids item = (ids)cmbshen.SelectedItem;

            int id1 = item.id;

            using (SqlConnection coon = new SqlConnection(@"Data Source=(LocalDB)\v11.0;AttachDbFilename=E:\新建文件夹\exam\test9\SQLtest9.mdf;Integrated Security=True"))

            {

                coon.Open();

                using (SqlCommand cmd = coon.CreateCommand())

                {

                    cmd.CommandText = "select * from city where id=@id";

                    cmd.Parameters.Add(new SqlParameter("@id", id1));

                    using (SqlDataReader reader = cmd.ExecuteReader())

                    {

                        while (reader.Read())

                        {

                            ids shi=new ids();

                            cmbshi.Items.Add(reader.GetString(reader.GetOrdinal("市")));

                            

                        }



                    }

                }



            }

           

        }



        private void cmbshi_SelectedIndexChanged(object sender, EventArgs e)

        {

            string shi = (string)cmbshi.SelectedItem;

            using (SqlConnection coon = new SqlConnection(@"Data Source=(LocalDB)\v11.0;AttachDbFilename=E:\新建文件夹\exam\test9\SQLtest9.mdf;Integrated Security=True"))

            {

                coon.Open();

                using (SqlCommand cmd = coon.CreateCommand())

                {

                    cmd.CommandText = "select * from city where 市=@id";

                    cmd.Parameters.Add(new SqlParameter("@id", shi));

                    using (SqlDataReader reader = cmd.ExecuteReader())

                    {

                        while (reader.Read())

                        {

                            

                           txtqh.Text=reader.GetString(reader.GetOrdinal("quhao"));



                        }



                    }

                }



            }

        }

    }

    class ids

    {

       public int id{get;set;}

       public string shen { get; set; }

    }

}