Springboot使用Pagehelper时thymeleaf遍历each时的问题、视图model无法正常遍历问题、thymeleaf Pagehelper 分页遍历出错

浅浅的花香味﹌ 2022-12-06 05:23 126阅读 0赞

# 使用th:each时，用常规惯性思维遍历出错 #

controller返回的不是一个实体对象，所以不能直接遍历，要调用pageinfo的list方法遍历

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNDcyODc3_size_16_color_FFFFFF_t_70_pic_center]

正确的遍历写法：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNDcyODc3_size_16_color_FFFFFF_t_70_pic_center 1]  
最后补充一下pagehelper代码：  
controller:

//分页查询数据
        @GetMapping("/findall")
        public String usermanage(Model model,
                                 @RequestParam(required = false,defaultValue="1",value="pageNum")Integer pageNum,
                                 @RequestParam(defaultValue="5",value="pageSize")Integer pageSize){ 
            //为了程序的严谨性，判断非空：
            if(pageNum == null){ 
                pageNum = 1;   //设置默认当前页
            }
            if(pageNum <= 0){ 
                pageNum = 1;
            }
            if(pageSize == null){ 
                pageSize = 5;    //设置默认每页显示的数据数
            }
            System.out.println("当前页是："+pageNum+"显示条数是："+pageSize);
    
            //1.引入分页插件,pageNum是第几页，pageSize是每页显示多少条,默认查询总数count
            PageHelper.startPage(pageNum,pageSize);
            //2.紧跟的查询就是一个分页查询-必须紧跟.后面的其他查询不会被分页，除非再次调用PageHelper.startPage
            try { 
                List<User> all = userMapper.findAll();
                System.out.println("分页数据："+all);
    
                //3.使用PageInfo包装查询后的结果,5是连续显示的条数,结果list类型是Page<E>
                PageInfo<User> userPageInfo = new PageInfo<User>(all, pageSize);
                //4.使用model/map/modelandview等带回前端
                model.addAttribute("guys",userPageInfo);
            }finally { 
                PageHelper.clearPage(); //清理 ThreadLocal 存储的分页参数,保证线程安全
            }
            //5.设置返回的jsp/html等前端页面
            // thymeleaf默认就会拼串classpath:/templates/xxxx.html
            return "list";
        }

html:

<div class="modal-footer no-margin-top">
                    <div class="col-md-6">
                        当前第 [[${ guys.pageNum}]]页,共 [[${ guys.pages}]] 页.一共 [[${ guys.total}]] 条记录
                    </div>
    
                    <ul class="pagination pull-right no-margin">
                        <li th:if="${guys.hasPreviousPage}">
                            <a th:href="'/usermanage?pageNum=1'">首页</a>
                        </li>
    
                        <li class="prev" th:if="${guys.hasPreviousPage}">
                            <a th:href="'/usermanage?pageNum='+${guys.prePage}">
                                <i class="ace-icon fa fa-angle-double-left"></i>
                            </a>
                        </li>
                        
                        <li th:each="nav:${guys.navigatepageNums}">
                            <a th:href="'/usermanage?pageNum='+${nav}" th:text="${nav}" th:if="${nav != guys.pageNum}"></a>
                            <span style="font-weight: bold;background: #6faed9;" th:if="${nav == guys.pageNum}" th:text="${nav}" ></span>
                        </li>
    
                        <li class="next" th:if="${guys.hasNextPage}">
                            <a th:href="'/usermanage?pageNum='+${guys.nextPage}">
                                <i class="ace-icon fa fa-angle-double-right"></i>
                            </a>
                        </li>
    
                        <li>
                            <a th:href="'/usermanage?pageNum='+${guys.pages}">尾页</a>
                        </li>
                    </ul>
                </div>
    
                <div>当前页号：<span th:text="${guys.pageNum}"></span></div>
                <div>每页条数：<span th:text="${guys.pageSize}"></span></div>
                <div>起始行号：<span th:text="${guys.startRow}"></span></div>
                <div>终止行号：<span th:text="${guys.endRow}"></span></div>
                <div>总结果数：<span th:text="${guys.total}"></span></div>
                <div>总页数：<span th:text="${guys.pages}"></span></div>
                <hr />
                <div>是否为第一页：<span th:text="${guys.isFirstPage}"></span></div>
                <div>是否为最后一页：<span th:text="${guys.isLastPage}"></span></div>
                <div>是否有前一页：<span th:text="${guys.hasPreviousPage}"></span></div>
                <div>是否有下一页：<span th:text="${guys.hasNextPage}"></span></div>

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