Cet exemple partage le code spécifique de la cascade provinciale et municipale de Java pour votre référence. Le contenu spécifique est le suivant
1.LoadaReaservlet.java
package com.scce.servlet; Importer java.io.ioException; import java.io.printwriter; import java.util.arraylist; import javax.servlet.servletException; import javax.servlet.http.httpservlet; import javax.servlet.http.httpservletRequest; javax.servlet.http.httpservletResponse; import net.sf.json.jsonArray; import com.scce.pojo.city; import com.scce.pojo.prov; classe publique LoadAreAservlet étend httpServlet {private static final long SerialVersionUID = 1l; public void doGet (demande httpservletRequest, réponse httpservletResponse) lève ServletException, ioException {this.dopost (demande, réponse); } public void doPost (requête HttpServletRequest, réponse httpservletResponse) lève ServletException, ioException {réponse.setContentType ("text / html; charset = utf-8"); request.SetcharAtterencoding ("UTF-8"); Printwriter out = réponse.getWriter (); ArrayList <vric> provs = new ArrayList <Pur> (); String provinceId = request.getParameter ("provinceId"); if (provinceId == "" || provinceId == null) {System.out.println ("Chargement des informations sur la ville au niveau de la préfecture"); Prom pro1 = new Prov (); pro1.setid (0); pro1.setProvinceName ("Hubei"); Pro pro pro2 = new prov (); pro2.SetId (1); pro2.SetProvincename ("Hunan"); Pro prot3 = new prov (); pro3.setid (2); pro3.setProvincename ("Guangdong"); Pro pro pro4 = new prov (); pro4.setid (3); pro4.setProvinceName ("guangxi"); provs.Add (pro1); provs.Add (pro2); pro.Add (pro3); pro.Add (pro4); System.out.println (JSONArray.FromObject (Provs) .ToString ()); // [{"id": 0, "provinceName": "Hubei"}, {}] out.print (jsonArray.fromObject (pros) .toString ()); } else {ArrayList <City> Cities = new ArrayList <Agity> (); if (provinceId.equals ("0")) {City City1 = New City (); City1.setid (0); City1.setCityName ("Wuhan City"); City City2 = New City (); City2.setid (1); City2.SetCityName ("City Huangshi"); City City3 = New City (); City3.setid (2); City3.SetCityName ("Shiyan City"); Citys.Add (City1); villes.add (City2); villes.add (City3); } if (provinceId.equals ("1")) {City City1 = new City (); City1.setid (0); City1.setCityName ("Changsha City"); City City2 = New City (); City2.setid (1); City2.SetCityName ("Yueyang City"); City City3 = New City (); City3.setid (2); City3.SetCityName ("Xiangtan City"); villes.add (City1); villes.add (City2); villes.add (City3); } System.out.println (jsonArray.FromObject (Citys) .ToString ()); Out.print (JSONArray.fromObject (Citys) .ToString ()); }}} 2.Test1.html
<! DocType HTML> <HTML> <A-HEAD> <TITME> Chapter4-Test1 </Title> <Meta Http-Equiv = "Keywords" Content = "Keyword1, Keyword2, Keyword3"> <Meta Http-Equiv = "Description" Content = "Il s'agit de ma page"> <Meta http-equiv = "Contenu-Type-Type" Contenu = "Text / http-equiv =" Contenu-Type-Type "Content-Type" charset = utf-8 "> <link rel =" Stylesheet "href =" ../ ui / themes / icon.css "type =" text / css "> </ link> <link rel =" Stylesheet "href =" ../ ui / themes / default / easyui.css "type =" text / css "> </ link> <! - <! src = "../ js / jQuery-1.8.2.min.js"> </ script> -> <script type = "text / javascript" src = "../ ui / jQuery.min.js"> </ script> <script type = "text / javascrip type = "text / javascript" src = "../ ui / jquery.easyui.min.js"> </ script> <script type = "text / javascrip DataCombObox = [{"id": 1, "ProvinceName": "Province de Hubei"}, {"id": 2, "ProvinceName": "Province de Hunan", "Selected": true}, {"id": 3, "provincename": "Hebei Province"}, {id ": 4," Provincename ":" Henan ". * / $ (function () {$ ("# province"). ComboBox ({width: 150, ValueField: 'Id', // 1 TextField: 'ProvinceName', // Hubei Province modifiable: false, // data: datacombox // spécifiez la source de données URL pour la liste drop-down: '../Offorce de chargement' provid = $ ("# province"). ComboBox (GetValue "); Function LoadCity (Provid) {$ ("# City"). ComboBox ({Width: 150, ValueField: 'Id', // 1 TextField: 'CityName', // Hubei Province Editable: False, // Données: DataCombOx // Spécifiez la source de données URL pour la liste de drop-down: '../ Loadareasert? } </ script> </ head> <body> province: <select id = "province"> <option value = "0"> Les données chargent .. </ option> </ select> <br/> city: <select id = "city"> <option value = ""> Les données sont chargées .. </ option> </ select> </ body> </html>Ce qui précède concerne cet article, j'espère qu'il sera utile pour tout le monde d'apprendre la programmation Java.