實現從數據庫中動態獲取對應的List集合，並在Easyui的combobox中顯示出來。
實現的效果如下：
1、數據庫的表設計如圖所示
2、數據庫中填寫相關的數據，如圖所示。如圖所示【法律法規】是所屬欄目，因此他的字段parentid是0。 【中國公民出國】、【內地居民往來港澳】是屬於法律法規的類別。因此他們的字段parentid是對應1，【法律法規】的字段categoryid是1.
3、相關的配置：已經在前面的博客中寫了//www.VeVB.COm/article/86381.htm
這裡就不多寫。只把關鍵代碼貼出來。
4、對應的Action代碼
package crj.portal.web.management.action;import java.io.IOException;import java.util.List;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import net.sf.json.JSONArray;import net.sf.json.JSONObject;import net.sf.json.JsonConfig;import org.apache.log4j.Logger;import org.apache.struts2.ServletActionContext;import org.hibernate.Criteria;import org.hibernate.criterion.Order;import com.sun.tools.javac.util.Log;import crj.portal.web.management.model.Cpersontypetbl;import crj.portal.web.management.service.CategoryService;import crj.portal.web.management.service.ItemService;import crj.portal.web.management.service.UserService;public class ItemManageAction { Logger log=Logger.getLogger(this.getClass()); private String page; private String rows; private String lanmuid; private ItemService itemService;// 依賴注入//下拉框--查詢欄目public String categorytbl() throws Exception{ List list=itemService.queryLanMu(); this.toJsonArray(list); return null; } //根據欄目的ID 查詢擁有的類別public String leibie() throws Exception{ List list=itemService.queryLeiBie(lanmuid); this.toJsonArray(list); return null; } public String toJsonArray(List list) throws IOException{ HttpServletResponse response = ServletActionContext.getResponse(); HttpServletRequest request = ServletActionContext.getRequest(); JSONArray json = JSONArray.fromObject(list); log.info("JSON格式：" +json.toString()); response.setCharacterEncoding("utf-8");// 指定為utf-8 response.getWriter().write(json.toString());// 轉化為JSOn格式return null; } public String save() throws Exception { return this.alllist(); } public ItemService getItemService() { return itemService; } public void setItemService(ItemService itemService) { this.itemService = itemService; } public String getPage() { return page; } public void setPage(String page) { this.page = page; } public String getRows() { return rows; } public void setRows(String rows) { this.rows = rows; } public UserService getUserService() { return userService; } public void setUserService(UserService userService) { this.userService = userService; } public CategoryService getCategoryService() { return categoryService; } public void setCategoryService(CategoryService categoryService) { this.categoryService = categoryService; } public String getLanmuid() { return lanmuid; } public void setLanmuid(String lanmuid) { this.lanmuid = lanmuid; } } 5、對應的接口代碼
public interface ItemService { //下拉框--查詢欄目public List queryLanMu() throws Exception; //下拉框--查詢類別public List queryLeiBie(String ids) throws Exception; } 6、對應的接口實現類代碼
public class ItemServiceImpl implements ItemService { Logger log = Logger.getLogger(this.getClass()); private SessionFactory sessionFactory; //下拉框--查詢欄目public List queryLanMu() throws Exception { Criteria criteria=this.sessionFactory.getCurrentSession().createCriteria(Categorytbl.class); criteria.add(Restrictions.eq("parentid", 0)); criteria.addOrder(Order.asc("categoryid")); return criteria.list(); } //下拉框--查詢類別public List queryLeiBie(String ids) throws Exception { int i=Integer.parseInt(ids); Criteria criteria=this.sessionFactory.getCurrentSession().createCriteria(Categorytbl.class); criteria.add(Restrictions.eq("parentid", i)); criteria.addOrder(Order.asc("categoryid")); return criteria.list(); } public SessionFactory getSessionFactory() { return sessionFactory; } public void setSessionFactory(SessionFactory sessionFactory) { this.sessionFactory = sessionFactory; }} 7、對應的JSP代碼
<%@ page language="java" errorPage="/error.jsp" pageEncoding="utf-8"%><%@ taglib prefix="s" uri="/struts-tags"%><% String path = request.getContextPath();%><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><title>信息管理</title><!-- 引入Jquery --><script type="text/javascript" src="<%=path%>/easyui_1.3.2/jquery-1.8.0.min.js" charset="utf-8"></script><!-- 引入Jquery_easyui --><script type="text/javascript" src="<%=path%>/easyui_1.3.2/jquery.easyui.min.js" charset="utf-8"></script><!-- 引入easyUi國際化--中文--><script type="text/javascript" src="<%=path%>/easyui_1.3.2/locale/easyui-lang-zh_CN.js" charset="utf-8"></script><!-- 引入easyUi默認的CSS格式--藍色--><link rel="stylesheet" type="text/css" href="<%=path%>/easyui_1.3.2/themes/default/easyui.css" /><!-- 引入easyUi小圖標--><link rel="stylesheet" type="text/css" href="<%=path%>/easyui_1.3.2/themes/icon.css" /><script type="text/javascript"> /* 初始化下載表格信息*/ $(function() { // 下拉框選擇控件，下拉框的內容是動態查詢數據庫信息$('#lanmu').combobox({ url:'itemManage!categorytbl', editable:false, //不可編輯狀態cache: false, panelHeight: 'auto',//自動高度適合valueField:'categoryid', textField:'categoryName', onHidePanel: function(){ $("#leibie").combobox("setValue",''); var lanmuid = $('#lanmu').combobox('getValue'); $.ajax({ type: "POST", url: "itemManage!leibie?lanmuid="+lanmuid, cache: false, dataType : "json", success: function(data){ $("#leibie").combobox("loadData",data); } }); } }); $('#leibie').combobox({ //url:'itemManage!categorytbl', editable:false, //不可編輯狀態cache: false, panelHeight: 'auto',//自動高度適合valueField:'categoryid', textField:'categoryName' }); });</script></head><body> <!-- 工具攔--> <div id="tb" style="padding: 3px"> <form > <span>所屬欄目:</span> <select id="lanmu"> </select> <span>類別:</span> <select id="leibie"> </select> </form> </div> </body></html>以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持武林網。