全国省市县三级联动（数据完整版）
网页前台代码：
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" EnableEventValidation="false"%><%@ Register assembly="AjaxControlToolkit" namespace="AjaxControlToolkit" tagprefix="cc1" %><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head runat="server"> <title>无标题页</title></head><body> <form id="form1" runat="server"> <div align="center"> <asp:ScriptManager ID="ScriptManager1" runat="server"> </asp:ScriptManager> <fieldset > <legend>全国省市县</legend> <fieldset style="width: 265px"> <legend>省</legend> <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True"> </asp:DropDownList> <cc1:CascadingDropDown ID="DropDownList1_CascadingDropDown" runat="server" Category="provice" Enabled="True" LoadingText="读取数据中
.." PromptText="请选择省" TargetControlID="DropDownList1" ServicePath="WebService.asmx" ServiceMethod="GetproviceNames"> </cc1:CascadingDropDown> </fieldset> <fieldset style="width: 266px"> <legend>市</legend> <asp:DropDownList ID="DropDownList2" runat="server" AutoPostBack="True"> </asp:DropDownList> <cc1:CascadingDropDown ID="DropDownList2_CascadingDropDown" runat="server" Category="city" Enabled="True" TargetControlID="DropDownList2" LoadingText="读取数据中.." PromptText="请选择市" ParentControlID="DropDownList1" ServicePath="WebService.asmx" ServiceMethod="GetCityNames"> </cc1:CascadingDropDown> </fieldset> <fieldset style="width: 266px"> <legend>县</legend> <asp:DropDownList ID="DropDownList3" runat="server"> </asp:DropDownList> <cc1:CascadingDropDown ID="DropDownList3_CascadingDropDown" runat="server" Category="District" TargetControlID="DropDownList3" Enabled="True" LoadingText="读取数据中.." ParentControlID="DropDownList2" ServicePath="WebService.asmx" ServiceMethod="GetDistrictNames"> </cc1:CascadingDropDown> </fieldset> </fieldset> </div> </form></body></html>using System;using System.Collections;using System.Linq;using System.Web;using System.Web.Services;using System.Web.Services.Protocols;using System.Xml.Linq;//访问数据库命名空间using System.Data;using System.Data.SqlClient;//访问web.config命名空间using System.Web.Configuration;//导入ScriptServiceAttribute类的命名空间using System.Web.Script.Services;//返回CascadingDropDownNameValue数组所需的命名空间using AjaxControlToolkit;using System.Collections.Generic;using System.Collections.Specialized;
/// <summary>
///WebService 的摘要说明
/// </summary>[WebService(Namespace = "http://tempuri.org/")][WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]//若要允许使用 ASP.NET AJAX 从脚本中调用此 Web 服务，请取消对下行的注释。 [System.Web.Script.Services.ScriptService]public class WebService : System.Web.Services.WebService{ public WebService()
{
//如果使用设计的组件，请取消注释以下行 //InitializeComponent(); 
} [WebMethod] public CascadingDropDownNameValue[] GetproviceNames(string knownCategoryValues, string category) { List<CascadingDropDownNameValue> values = new List<CascadingDropDownNameValue>(); SqlConnection conn = new SqlConnection(WebConfigurationManager.ConnectionStrings["Personal"].ConnectionString); SqlCommand comm = conn.CreateCommand(); comm.CommandText = "select [ProvinceID],[ProvinceName] from [S_Province] order by 1"; conn.Open(); try { SqlDataReader dr = comm.ExecuteReader(); while (dr.Read()) { values.Add(new CascadingDropDownNameValue(dr[1].ToString(), dr[0].ToString())); } return values.ToArray(); } finally { conn.Close(); } } [WebMethod] public CascadingDropDownNameValue[] GetCityNames(string knownCategoryValues, string category) { StringDictionary kcv = CascadingDropDown.ParseKnownCategoryValuesString(knownCategoryValues); if (!kcv.ContainsKey("provice")) { return null; } List<CascadingDropDownNameValue> values = new List<CascadingDropDownNameValue>(); SqlConnection conn = new SqlConnection(WebConfigurationManager.ConnectionStrings["Personal"].ConnectionString); SqlCommand comm = conn.CreateCommand(); comm.CommandText = "select [CityID],[CityName] from [S_City] where [ProvinceID]=@ProvinceID order by 1"; comm.Parameters.Add("@ProvinceID", SqlDbType.Int).Value = kcv["provice"]; conn.Open(); try { SqlDataReader dr = comm.ExecuteReader(); while (dr.Read()) { values.Add(new CascadingDropDownNameValue(dr[1].ToString(), dr[0].ToString())); } return values.ToArray(); } finally { conn.Close(); } } [WebMethod] public CascadingDropDownNameValue[] GetDistrictNames(string knownCategoryValues, string category) { StringDictionary kcv = CascadingDropDown.ParseKnownCategoryValuesString(knownCategoryValues); if (!kcv.ContainsKey("city")) { return null; } List<CascadingDropDownNameValue> values = new List<CascadingDropDownNameValue>(); SqlConnection conn = new SqlConnection(WebConfigurationManager.ConnectionStrings["Personal"].ConnectionString); SqlCommand comm = conn.CreateCommand(); comm.CommandText = "select [DistrictID],[DistrictName] from [S_District] where [CityID]=@CityID order by 1"; comm.Parameters.Add("@CityID", SqlDbType.Int).Value = kcv["city"]; conn.Open(); try { SqlDataReader dr = comm.ExecuteReader(); while (dr.Read()) { values.Add(new CascadingDropDownNameValue(dr[1].ToString(), dr[0].ToString())); } return values.ToArray(); } finally { conn.Close(); } }} 数据库脚本下载链接：
