實現查詢分頁以及隔行變色
阿新 • • 發佈：2019-01-23
在網頁的顯示中，經常需要用到將查詢到的資訊顯示在頁面上，當查詢到的資訊較多時，需要用到分頁查詢，將資訊分頁顯示，為了區分每一行，所以要設定一個隔行換色的特效。Hibernate的Query物件提供了分頁查詢的功能，是setFirstResult和setMaxResults用於設定查詢記錄的第一條記錄和每一也最大記錄數，然後使用query.list()方法獲取該頁相關資訊。
下面看具體程式碼，首先使用Page類封裝分頁查詢的相關資訊：
然後看dao類的具體處理方法package tool; import java.util.List; public class Page { private int currentPage;//當前頁碼 private int totalSize;//總記錄數 private int totalPage;//總頁數 private boolean hasPrevious;//是否有前一頁 private boolean hasNext;//是否有後一頁 private List list;//存放查詢結果集合資訊 //省略set和get方法 }
然後就將分頁查詢的具體資訊放到page物件中，然後再Action類中將page物件放到request中並返回到顯示介面，然後再顯示介面進行相應處理後實現分頁顯示，具體資訊顯示頁面如下：import java.util.List; import model.Student; import org.hibernate.Query; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.springframework.transaction.annotation.Transactional; import tool.Page; public class BaseDao { private SessionFactory sessionfactory; public SessionFactory getSessionfactory() { return sessionfactory; } public void setSessionfactory(SessionFactory sessionfactory) { this.sessionfactory = sessionfactory; } @Transactional public Page query(int currentPage,int pageSize){ Page page = new Page(); Session session = sessionfactory.getCurrentSession(); String hql = "FROM Student s order by s.id"; Query query = session.createQuery(hql); List<Student> list = query.list(); int count = list.size(); //計算總頁數 int totalpage = (count%pageSize==0)?(count/pageSize):(count/pageSize+1); //判斷當前頁碼是否有上下頁 if(currentPage>=totalpage){ currentPage=totalpage; page.setHasNext(false); }else{ page.setHasNext(true); } if(currentPage <=1){ currentPage = 1; page.setHasPrevious(false); }else{ page.setHasPrevious(true); } query.setFirstResult((currentPage-1)*pageSize); query.setMaxResults(pageSize); List<Student> result = query.list(); page.setCurrentPage(currentPage); page.setList(result); page.setTotalPage(totalpage); page.setTotalSize(count); return page; } }
對於隔行變色可以設定<s：iterator>標籤的status屬性，判斷狀態時奇數行還是偶數行。例如:<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <%@ taglib uri = "/struts-tags" prefix="s" %> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>查詢結果</title> </head> <body> <div align="center"> <s:if test="#request.show.list.size !=0"> <table border="1"> <tr> <td>id</td> <td>姓名</td> </tr> <s:iterator value="#request.test.list" var="tes"> <tr> <td> <s:property value="#tes.id"/> </td> <td> <s:property value="#tes.name"/> </td> </tr> </s:iterator> <tr> <td colspan="2" align="center"> <a href="test?page=1">首頁</a>| <s:if test="#request.test.hasPrevious"> <a href="test?page=<s:property value='#request.test.currentPage-1'/>"> 上一頁</a> </s:if> <s:if test="#request.test.hasNext"> |<a href="test?page=<s:property value='#request.test.currentPage+1'/>"> 下一頁</a> </s:if> |<a href="test?page=<s:property value='#request.test.totalPage'/>"> 末頁</a> 第<s:property value="#request.test.currentPage"/>頁/ 共<s:property value="#request.test.totalPage"/>頁 （<s:property value="#request.test.totalSize"/>條記錄） </td> </tr> </table> </s:if> </div> </body> </html>
<s:iterator value="#request.records.list" var="tr" status="status">
<s:if test="#status.even">
<tr bgcolor="yellow">
</s:if>
<s:if test="#status.odd">
<tr bgcolor="blue">
</s:if>
<td><s:property value="#tr.transaction_date"/></td>
<td><s:property value="#tr.expense"/></td>
<td><s:property value="#tr.income"/></td>
<td><s:property value="#tr.balance"/></td>
<td><s:property value="#tr.transaction_type"/></td>
<td><s:property value="#tr.remark"/></td>
</tr>
</s:iterator>