OA项目 分页功能总结一 简单的分页(资料来源于传智播客汤阳光的视频教程）

1.在domain包中新建一个PageBean类

其主要的属性有：

//已知

private int currentPage //当前页

private int pageSize //每页数据条数,默认为10条

//需要查询数据库的

private int recodCount //总记录数

private List recordList //当前页所需要的数据列表

//计算

private int pageCount //总页面数

private int startPageIndex; // 页码显示的起始页

private int endPageIndex; //页码显示的结束页

public PageBean(int currentPage,int pageSize,List recordList,int recordCount){

pageCount=(recordCount+pageSize-1)/pageSize;

if(pageCount<10){

startPageIndex=1;

endPageIndex=pageCount;

}

else{

startPageIndex=currentPage-4;

endPageIndex=currentPage+5;

if( startPageIndex<1){

startPageIndex=1;

endPageIndex=10;

}

if(endPageIndex>pageCount){endPageIndex=pageCount;startPageIndex=pageCount-9;}

}

}

生成相应的set和get方法，这里省略。。。。

以下代码段的pagebean类的内容是我做项目的代码，和上面不一定完全相同

package cn.itcast.oa.domain;

import java.util.List;

public class PageBean {
//查询
private int recordCount;  //总记录数
private List recordList;  //本页数据列表

//传递的参数
private int currentPage;   //当前页
private int pageSize;      //当前页记录数

//计算
private int pageCount;   //总页数
private int beginPageIndex;//开始的页面索引
private int endPageIndex;//结束的页面索引

public PageBean(int currentPage, int pageSize, List recordList,int recordCount) {
this.currentPage = currentPage;
this.pageSize = pageSize;
this.recordList=recordList;
this.recordCount=recordCount;

//计算
pageCount=(recordCount+pageSize-1)/pageSize;
if(pageCount<10){
beginPageIndex=1;
endPageIndex=pageCount;
}
else{
beginPageIndex=currentPage-4;
endPageIndex=currentPage+5;
if(beginPageIndex<1){
beginPageIndex=1;
endPageIndex=10;
}
else if(endPageIndex>pageCount){
endPageIndex=pageCount;
beginPageIndex=pageCount-9;
}

}

}
public int getRecordCount() {
return recordCount;
}
public void setRecordCount(int recordCount) {
this.recordCount = recordCount;
}
public List getRecordList() {
return recordList;
}
public void setRecordList(List recordList) {
this.recordList = recordList;
}
public int getCurrentPage() {
return currentPage;
}
public void setCurrentPage(int currentPage) {
this.currentPage = currentPage;
}
public int getPageSize() {
return pageSize;
}
public void setPageSize(int pageSize) {
this.pageSize = pageSize;
}
public int getPageCount() {
return pageCount;
}
public void setPageCount(int pageCount) {
this.pageCount = pageCount;
}
public int getBeginPageIndex() {
return beginPageIndex;
}
public void setBeginPageIndex(int beginPageIndex) {
this.beginPageIndex = beginPageIndex;
}
public int getEndPageIndex() {
return endPageIndex;
}
public void setEndPageIndex(int endPageIndex) {
this.endPageIndex = endPageIndex;
}

}

2.在config包中新建一个Configuration类，用来设置和得到每页的记录数pageSize，默认是10条

Public Class Configuration(){

private static int pageSize;

static {
pageSize=10;
}

public static int getPageSize(){
return pageSize;
}

}

3.在相应的Action(如：UserAction)中，修改原先在list方法中的内容，改为：

private int pageNum;

生成相应的seter,geter方法，这里省略。。。

PageBean pageBean=userService.getPageBean(pageNum,user);

ActionContext.getContext.put("pageBean",pageBean);

4.在Service和ServiceImpl中生成以下方法并实现它：

public PageBean getPageBean(int pageNum){

int currentPage=pageNum;

int pageSize=Configuration.getPageSize();

//查询

List recordList=getSession.createQuery(//

"from User u ")//

.setFirstResults((currentPage-1)*pageSize)//

.setMaxResults(pageSize)//

.list();

int recordCount=getSession.createQuery(//

"select count(*) from User u ").list();

return new PageBean(currentPage,pageSize,recordList,recordCount);

}

5.在相应的页面中插入以下的名称：

如

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags"%>

<div id=PageSelectorBar>
<div id=PageSelectorMemo>
页次：${currentPage}/${pageCount}页  
每页显示：${pageSize }条  
总记录数：${recordCount }条
</div>
<div id=PageSelectorSelectorArea>

<a href="javascript: gotoPage(1)" title="首页" style="cursor: hand;">
<img src="${pageContext.request.contextPath}/style/blue/images/pageSelector/firstPage.png"/>
</a>

<s:iterator begin="%{beginPageIndex}" end="%{endPageIndex}" var="num">
<s:if test="currentPage == #num"><%-- 当前页 --%>
<span class="PageSelectorNum PageSelectorSelected">${num}</span>
</s:if>
<s:else><%-- 非当前页 --%>
<span class="PageSelectorNum" style="cursor: hand;" onClick="gotoPage(${num});">${num}</span>
</s:else>
</s:iterator>

<a href="javascript: gotoPage(${pageCount})" title="尾页" style="cursor: hand;">
<img src="${pageContext.request.contextPath}/style/blue/images/pageSelector/lastPage.png"/>
</a>

转到：
<select id="pn" onchange="gotoPage(this.value)">
<s:iterator begin="1" end="%{pageCount}" var="num">
<option value="${num}">${num}</option>
</s:iterator>
</select>
<script type="text/javascript">
// 回显页码
$("#pn").val(${currentPage});
</script>
<script type="text/javascript">
function gotoPage( pageNum ){
//window.location.href = "forumAction_show.action?id=${id}&pageNum=" + pageNum;
$(document.forms[0]).append("<input name='pageNum' type='hidden' value='"+pageNum+"' />");
document.forms[0].pageNum.value=pageNum;
document.forms[0].submit();
}
</script>

</div>
</div>

<!-- <script type="text/javascript">
function gotoPage( pageNum ){
window.location.href = "forumAction_show.action?id=${id}&pageNum=" + pageNum;

/* $(document.forms[0]).append("<input type='hidden' name='pageNum' value='" + pageNum + "'/>");
document.forms[0].submit(); // 提交表单 */
}
</script> -->

6.运行，简单的分页即可完成

由于这只是简单的分页功能，在之后我会持续更新分页功能的改进，以实现更加复杂的业务逻辑需求，敬请关注！！！