defaultcs.aspx.cs

Telerik是很大的第三方软件制造商

using System;
using System.Data;
using System.Data.OleDb;
using Telerik.QuickStart;
using Telerik.WebControls;

namespace Telerik.ComboboxExamplesCS.MultipleComboBoxes
{
	/// <summary>
	/// Summary description for _Default.
	/// </summary>
	public class DefaultCS: XhtmlPage
	{
		protected RadComboBox RadComboBox2;
		protected RadComboBox RadComboBox3;	
		protected RadComboBox RadComboBox1;		
		
		private void Page_Load(object sender, EventArgs e)
		{	
			if (!Page.IsPostBack)
			{
				LoadContinents();	
			}
		}
		

		#region Web Form Designer generated code
		override protected void OnInit(EventArgs e)
		{
			//
			// CODEGEN: This call is required by the ASP.NET Web Form Designer.
			//
			InitializeComponent();
			base.OnInit(e);
		}
		
		///		Required method for Designer support - do not modify
		///		the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{
			this.RadComboBox1.ItemsRequested += new Telerik.WebControls.RadComboBoxItemsRequestedEventHandler(this.RadComboBox1_ItemsRequested);
			this.RadComboBox2.ItemsRequested += new Telerik.WebControls.RadComboBoxItemsRequestedEventHandler(this.RadComboBox2_ItemsRequested);
			this.RadComboBox3.ItemsRequested += new Telerik.WebControls.RadComboBoxItemsRequestedEventHandler(this.RadComboBox3_ItemsRequested);
			this.Load += new System.EventHandler(this.Page_Load);

		}
		#endregion

		private void LoadContinents()
		{
			string path = Server.MapPath("~/Combobox/Data/Countries.mdb");
			OleDbConnection dbCon = new OleDbConnection ("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + path); 
			dbCon.Open();

			OleDbDataAdapter adapter = new OleDbDataAdapter("SELECT * FROM Continents", dbCon); 
			DataTable dt = new DataTable();
			adapter.Fill(dt);						
			dbCon.Close();

			RadComboBox1.DataTextField = "Name";
			RadComboBox1.DataValueField = "ID";
			RadComboBox1.DataSource = dt;
			RadComboBox1.DataBind();
			
			RadComboBox1.Items.Insert(0, new RadComboBoxItem("- Select a continent -"));			

			foreach (RadComboBoxItem item in RadComboBox1.Items)
			{
				item.ToolTip = item.Text;
			}
		}

		private void LoadCountries(string continentID)
		{
			string path = Server.MapPath("~/Combobox/Data/Countries.mdb");
			OleDbConnection dbCon = new OleDbConnection ("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + path); 
			dbCon.Open();

			OleDbDataAdapter adapter = new OleDbDataAdapter("SELECT * FROM Countries WHERE ContinentID=" + continentID, dbCon); 
			DataTable dt = new DataTable();
			adapter.Fill(dt);
			dbCon.Close();

			RadComboBox2.DataTextField = "Name";
			RadComboBox2.DataValueField = "ID";
			RadComboBox2.DataSource = dt;
			RadComboBox2.DataBind();

			foreach (RadComboBoxItem item in RadComboBox2.Items)
			{
				item.ToolTip = item.Text;
			}
		}

		private void LoadCities(string countryID)
		{
			string path = Server.MapPath("~/Combobox/Data/Countries.mdb");
			OleDbConnection dbCon = new OleDbConnection ("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + path); 
			dbCon.Open();

			OleDbDataAdapter adapter = new OleDbDataAdapter("SELECT * FROM Cities WHERE CountryID=" + countryID, dbCon); 
			DataTable dt = new DataTable();
			adapter.Fill(dt);
			dbCon.Close();

			RadComboBox3.DataTextField = "Name";
			RadComboBox3.DataValueField = "ID";
			RadComboBox3.DataSource = dt;
			RadComboBox3.DataBind();

			foreach (RadComboBoxItem item in RadComboBox3.Items)
			{
				item.ToolTip = item.Text;
			}
		}
		
		private void RadComboBox1_ItemsRequested(object o, RadComboBoxItemsRequestedEventArgs e)
		{
			LoadContinents();
		}

		private void RadComboBox2_ItemsRequested(object o, RadComboBoxItemsRequestedEventArgs e)
		{
			LoadCountries(e.Text);
		}

		private void RadComboBox3_ItemsRequested(object o, RadComboBoxItemsRequestedEventArgs e)
		{
			LoadCities(e.Text);
		}
	}
}