SSM整合实战【V2.0】---使用PageHelper新增分页功能

男娘i 2022-11-28 05:56 130阅读 0赞

### SSM整合实战【V2.0】---使用PageHelper新增分页功能 ###

*  一、分页插件PageHelper
 *  二、pageInfo类属性
 *  三、controller
 *  四、jsp
 *  四、books表记录
 *  四、效果截图

# 一、分页插件PageHelper #

**PageHelper是Mybatis一款分页插件，简单上手**

*  [PageHelper文档][PageHelper]

# 二、pageInfo类属性 #

public class PageInfo<T> implements Serializable { 
    private static final long serialVersionUID = 1L;
    //当前页
    private int pageNum;
    //每页的数量
    private int pageSize;
    //当前页的数量
    private int size;
    //由于startRow 和endRow 不常用，这里说个具体的用法
    //可以在页面中"显示startRow 到endRow 共size 条数据"
    //当前页面第一个元素在数据库中的行号
    private int startRow;
    //当前页面最后一个元素在数据库中的行号
    private int endRow;
    //总记录数
    private long total;
    //总页数
    private int pages;
    //结果集
    private List<T> list;
    //前一页
    private int prePage;
    //下一页
    private int nextPage;
    //是否为第一页
    private boolean isFirstPage = false;
    //是否为最后一页
    private boolean isLastPage = false;
    //是否有前一页
    private boolean hasPreviousPage = false;
    //是否有下一页
    private boolean hasNextPage = false;
    //导航页码数
    private int navigatePages;
    //所有导航页号
    private int[] navigatepageNums;
    //导航条上的第一页
    private int navigateFirstPage;
    //导航条上的最后一页
    private int navigateLastPage;
    }

# 三、controller #

@RequestMapping("/selectbookforpage")
        public ModelAndView selectBookForPage(@RequestParam(defaultValue="1")Integer currentPage){ 
            PageHelper.startPage(currentPage,5);
            //紧跟的一条查询语句会被分页
            //selectAllBooks : select * from books;
            List<Books> books = bookService.selectAllBooks();
            PageInfo pageInfo = new PageInfo(books,5);
            ModelAndView mv = new ModelAndView();
            mv.addObject("pageInfo",pageInfo);
            mv.setViewName("admin_book");
            return mv;
        }

# 四、jsp #

<div class="row clearfix">
                <div class="col-md-12">
                    <table class="table table-hover table-bordered">
                        <tr>
                            <th>书籍ID</th>
                            <th>书籍名称</th>
                            <th>书籍数量</th>
                            <th>书籍详情</th>
                            <th>操作</th>
                        </tr>
    
                        <c:forEach var="book" items="${pageInfo.list}">
                            <tr>
                            <td>${ book.bookID}</td>
                            <td>${ book.bookName}</td>
                            <td>${ book.bookCounts}</td>
                            <td>${ book.detail}</td>
                             <td>
                                 <a href="${pageContext.request.contextPath}/book/toupdatebook?bookID=${book.bookID}">修改</a>
                                  | 
                                 <a href="${pageContext.request.contextPath}/book/deletebook?bookID=${book.bookID}">删除</a>
                             </td>
                            </tr>
                        </c:forEach>
                    </table>
                </div>
            </div>
    
            <div style="float: left;font-size: 16px;width: 500px;height: 100px;margin-top: 15px">
                <span>共<span style="font-size: 19px;font-family: fantasy;color: cornflowerblue"> ${ pageInfo.total} </span>条记录,</span>
                <span>当前显示第<span style="font-size: 19px;font-family: fantasy;color: cornflowerblue"> ${ pageInfo.pageNum} </span>页,</span>
                <span>共<span style="font-size: 19px;font-family: fantasy;color: cornflowerblue"> ${ pageInfo.pages} </span>页</span>
            </div>
    
            <nav aria-label="Page navigation" style="float: right;">
                <ul class="pagination">
                    <c:if test="${pageInfo.hasPreviousPage}">
                        <li>
                            <a href="${pageContext.request.contextPath}/book/selectbookforpage?currentPage=${pageInfo.pageNum-1}" aria-label="Previous">
                                <span aria-hidden="true">«</span></a>
                        </li>
                    </c:if>
    
                    <c:if test="${pageInfo.hasPreviousPage == false}">
                        <li>
                            <a href="#">«</a>
                        </li>
                    </c:if>
    
    
                        <c:forEach items="${pageInfo.navigatepageNums}" var="page_num">
                            <c:if test="${page_num == pageInfo.pageNum}">
                                <li>
                                <a href="#">${ page_num}</a>
                                </li>
                            </c:if>
    
                            <c:if test="${page_num != pageInfo.pageNum}">
                                <li>
                                    <a href="${pageContext.request.contextPath}/book/selectbookforpage?currentPage=${page_num}">${ page_num}</a>
                                </li>
                            </c:if>
                        </c:forEach>
    
    
                    <c:if test="${pageInfo.hasNextPage}">
                    <li>
                        <a href="${pageContext.request.contextPath}/book/selectbookforpage?currentPage=${pageInfo.pageNum+1}" aria-label="Next">
                            <span aria-hidden="true">»</span>
                        </a>
                    </li>
                    </c:if>
    
                    <c:if test="${pageInfo.hasNextPage == false}">
                        <li>
                            <a href="#">»</a>
                        </li>
                    </c:if>
                </ul>
            </nav>

# 四、books表记录 #

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNDQyMzM1_size_16_color_FFFFFF_t_70_pic_center]

# 四、效果截图 #

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNDQyMzM1_size_16_color_FFFFFF_t_70_pic_center 1]

**再完善几个功能后公布源码，想要目前的源码可以私信我，我的代码永无bug！！！**

[PageHelper]: https://pagehelper.github.io/docs/howtouse/
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNDQyMzM1_size_16_color_FFFFFF_t_70_pic_center]: /images/20221124/c4d3ed03c20449b18d5ffb78910578d6.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNDQyMzM1_size_16_color_FFFFFF_t_70_pic_center 1]: /images/20221124/a76e1bbf59c64d9bb6b444ec97addc2c.png