Ado.Net实现简易（省、市、县）三级联动查询，还附加Access数据

1. 小弟在博客园驻园不久，初来咋到；将最近写的小程序附上，希望各位大牛们吐槽；激发对程序员围观的童鞋们，赶紧加入IT行业，如果你在上海那简称就是SHIT，哈哈题外话，以下开始切入正题：

坐公交车是旁边偶遇一小朋友，对我天朝区域不甚了解，为了偶的下一代不走回头路，激发爱国热情，故写下以下代码：

需求：

1. 读取本地数据库（文本、Access）;
2. 根据省、市、县数据库切换，显示子级、父级；

以下是成形图：

实现步骤：

1. 编写SqlHelper类（主要解决查询操作），代码如下

 private static readonly string accessConn = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + Directory.GetCurrentDirectory() + (@"\Areafull.accdb");

        /// <summary>
        /// 查询access数据，返回table
        /// </summary>
        /// <param name="sql">执行sql</param>
        /// <param name="parameters">查询参数</param>
        /// <returns></returns>
        public static DataTable ExecuteAccessDateTable(string sql, params SqlParameter[] parameters)
        {
            using (OleDbConnection cnn = new OleDbConnection(accessConn))
            {
                cnn.Open();
                using (OleDbCommand cmd = cnn.CreateCommand())
                {
                    cmd.CommandText = sql;
                    cmd.Parameters.AddRange(parameters);
                    OleDbDataReader apter = cmd.ExecuteReader();
                    DataTable dt = new DataTable();
                    dt.Load(apter);
                    return dt;
                }
            }
        }

2.界面设计

三个ListBox控件分别放入，省，市，县

       /// <summary>
       /// 初始化加载省数据
       /// </summary>
       /// <param name="sender"></param>
       /// <param name="e"></param>
        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            DataTable table = SqlHelper.ExecuteAccessDateTable("select * from areafull where AreaPid='0'");
            SlB.ItemsSource = GetAreas(table);//省份绑定
        }

        /// <summary>
        /// 省数据选择
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void SlB_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            Area areaRow = (Area)SlB.SelectedItem;
            DataTable table = SqlHelper.ExecuteDateTable("select * from areafull where AreaPid=@AreaPid", new SqlParameter("@AreaPid", areaRow.AreaId));
            SJBX.ItemsSource = GetAreas(table);
        }

        /// <summary>
        /// 市级数据选择
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void SJBX_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if (SJBX.SelectedItem != null)
            {
                Area areaRow = (Area)SJBX.SelectedItem;
                DataTable table = SqlHelper.ExecuteDateTable("select * from areafull where AreaPid=@AreaPid", new SqlParameter("@AreaPid", areaRow.AreaId));
                XJBX.ItemsSource = GetAreas(table);
            }
            else
            {
                XJBX.ItemsSource = null;
            }
        }

        /// <summary>
        /// 数据转换对象
        /// </summary>
        /// <param name="table"></param>
        /// <returns></returns>
        private List<Area> GetAreas(DataTable table)
        {
            List<Area> lst = new List<Area>();
            foreach (DataRow item in table.Rows)
            {
                Area are = new Area();
                are.AreaId = Convert.ToInt32(item["Areaid"]);
                are.AreaName = item["AreaName"].ToString();
                are.AreaPid = Convert.ToInt32(item["AreaPid"]);
                lst.Add(are);
            }
            return lst;
        }

总结：

1. 程序中主要用到数据转换对象的思想（Data——》Object）;
2. Ato.net本身提供的数据访问类；

需要数据库及源码的直接回复我

如在过程中提示未注册驱动，请到以下地址：下载安装即可

http://download.microsoft.com/download/7/0/3/703ffbcb-dc0c-4e19-b0da-1463960fdcdb/AccessDatabaseEngine.exe