实现省市连动.txt

学习积累的代码段

public class department : System.Web.UI.Page
	{
		protected System.Web.UI.WebControls.Label Label1;
		protected System.Web.UI.WebControls.DropDownList dd1;
		protected System.Web.UI.WebControls.Button Button1;
		protected System.Web.UI.WebControls.TextBox TextBox1;
		protected System.Web.UI.WebControls.ListBox ll1;
	
		private void Page_Load(object sender, System.EventArgs e)
		{//连接部门
			if (!Page.IsPostBack)
			{
				SqlConnection con=db.creatconnection();
				con.Open();
				SqlCommand  cmd =new SqlCommand("select *from department",con);
				SqlDataReader sdr =cmd.ExecuteReader();
				this.dd1.DataSource=sdr;
				this.dd1.DataTextField="depname";
				this.dd1.DataValueField="depid";
				this.dd1.DataBind();
				sdr.Close();
              //连接员工
				SqlCommand mycmd =new SqlCommand("select empid ,epname from  emp where depid="+this.dd1.SelectedValue,con);
				sdr=mycmd.ExecuteReader();
				this.ll1.DataSource=sdr;
				this.ll1.DataTextField="epname";
				this.ll1.DataValueField="empid";
				this.ll1.DataBind();
				sdr.Close();

               con.Close();

			
			}
	
			
			
		// 在此处放置用户代码以初始化页面
	}

		#region Web 窗体设计器生成的代码
		override protected void OnInit(EventArgs e)
		{
			//
			// CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。
			//
			InitializeComponent();
			base.OnInit(e);
		}
		
		/// <summary>
		/// 设计器支持所需的方法 - 不要使用代码编辑器修改
		/// 此方法的内容。
		/// </summary>
		private void InitializeComponent()
		{    
			this.dd1.SelectedIndexChanged += new System.EventHandler(this.dd1_SelectedIndexChanged);
			this.ll1.SelectedIndexChanged += new System.EventHandler(this.ll1_SelectedIndexChanged);
			this.Button1.Click += new System.EventHandler(this.Button1_Click);
			this.Load += new System.EventHandler(this.Page_Load);

		}
		#endregion

		private void dd1_SelectedIndexChanged(object sender, System.EventArgs e)
		{//实现部门员工的连动功能
			string  depid=this.dd1.SelectedValue;
			SqlConnection con=db.creatconnection();
			con.Open();
			SqlCommand mycmd =new SqlCommand("select empid ,epname from  emp where depid="+depid,con);
			SqlDataReader  sdr=mycmd.ExecuteReader();
			this.ll1.DataSource=sdr;
			this.ll1.DataTextField="epname";
			this.ll1.DataValueField="empid";
			this.ll1.DataBind();
			sdr.Close();
			con.Close();
		}

		private void ll1_SelectedIndexChanged(object sender, System.EventArgs e)
		{  

			

		}

		private void Button1_Click(object sender, System.EventArgs e)
		{
			TextBox1.Text=this.dd1.SelectedItem.ToString()+"     "+this.ll1.SelectedItem.ToString();
		}

		
		}
	}