jsp:使用jsp完成数据的分页显示

Posted 2020-10-20 dYb

一，使用jsp将数据库内的数据。分页显示到页面

1，创建一个servelt处理后台数据，和数据库的数据

private static final long serUid=1L;
    //加载驱动
    static final String jdbc="com.mysql.jdbc.Driver";
    //要连接的数据库url
    static final String db_url="jdbc:mysql://localhost:3306/test";
    //数据库用户名
    static final String user="db";
    //数据库密码
    static final String pass="1743721";
    int currentPage=1;
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        
        Connection conn=null;
        Statement stmt=null;
        //显示的数据的格式
        response.setContentType("text/html;charset=UTF-8");
        
        PrintWriter out =response.getWriter();
        try {
            Class.forName(jdbc);
            conn=DriverManager.getConnection(db_url,user,pass);
            stmt=conn.createStatement();
            String sql=null;
            sql="select * from t_message where 1=1 order by s_date desc";
            int pageSize=5;
            int d=3;
            String re=null;
　　　　　　　　//接收url中的参数
            re=request.getQueryString();
            //System.out.print(re);
            if(re!=null){
                String[] ee=re.split("=");
                if("cupg".equals(ee[0])){
                    re=ee[1];
                    int r=Integer.valueOf(re).intValue();
                    d=r;
                    currentPage=r;
                }else{
                    re=ee[1];
                    int bt=Integer.valueOf(re).intValue();
                    currentPage=bt;
                    if(bt<=3){
                        d=3;
                    }else{
                        d=bt;
                    }
                }
            }
            if(currentPage<=0){
                d=3;
                currentPage=1;
            }
            
            int start=(currentPage-1)*pageSize;
　　　　　　　　//获取数据进行分页处理
            String limitsql="select * from("+sql+")pp limit "+start+","+pageSize;
            ResultSet rs=stmt.executeQuery(limitsql);
            List<User> userlist=new ArrayList<User>();
            User user=null;
            
            while(rs.next()){
　　　　　　　　//创建一个对象存入数据
            user=new User();
            user.setMessage_id(rs.getInt("message_id"));
            user.setTitle(rs.getString("title"));
            user.setName(rs.getString("name"));
            user.setS_date(rs.getString("s_date"));
            user.setS_des(rs.getString("s_des"));
            user.setL_des(rs.getString("l_des"));
            userlist.add(user);
            }
            request.setAttribute("nubtn",d);
            request.setAttribute("cupg", currentPage);
            request.setAttribute("args", userlist);
            request.getRequestDispatcher("/qh/message.jsp").forward(request, response);
            
            //关闭通道
            rs.close();
            conn.close();
            stmt.close();
            
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
    }

2,在页面接收并处理得到的数据

    <div class="column">
        <h1 class="column-tit"><span><a href="#" title="首页">首页</a> > <a href="#" title="留言回复">留言回复</a></span>留言回复</h1>
        <div class="mailbox mt20">

                   <% ArrayList userlist=(ArrayList)request.getAttribute("args");
　　　　　　　　　　　　　　//遍历的到的数据
                       for(int i=0;i<userlist.size();i++){
                               User user=(User)userlist.get(i);
                    %>
                        <div class="online-content clearfix">
                            <div class="icon fl">
                                <img src="../images/online.png" alt="">
                            </div>
                            <div class="question fr">
                                <p>留言主题：<%=user.getTitle()%> </p>
                                <p class="name"><span>网友：<%=user.getName()%></span><span><%=user.getS_date()%></span><span><a target="_blank" href="#">我要留言</a></span></p>
                                <div class="message-i ">
                                    <p><strong>留言详情：</strong><%=user.getS_des()%></p>
                                </div>
                                <div class="answer">
                                    <p><strong>执法监察总队回复：</strong><%=user.getL_des()%></p>
                                </div>
                            </div>
                        </div>
                    <%
                        }
                    %>

              <div class="page">
　　　　　　　　　　
　　　　　　　　　　　　//分页按钮的处理
                   <%int currentPage=(Integer)request.getAttribute("cupg"); 
                           int cugg=3;
                           Integer d=0;
                            int nubtn=(Integer)request.getAttribute("nubtn");
                           if(nubtn>=3)cugg=nubtn;
                         String a=request.getQueryString();
                         if(a!=null){ 
                            String[] ee=a.split("=");
                            a=ee[1];
                        
                        d=Integer.parseInt(a);
                        }
                        
                       %>

            <div style="display: none;" id="yc"><%=a%></div>
            <ul id="mu"><li class="num"><a href="/MysqlTest/servlet/GetMysql?cupg=1">首页</a></li>
                    <li class="num"><a href="/MysqlTest/servlet/GetMysql?cupg=<%=currentPage-1%>">上一页</a></li>
                    <li class="num page-active"><a href="/MysqlTest/servlet/GetMysql?nubtn=<%=cugg-2%>"><%=cugg-2%></a></li>
                    <li class="num" style=""><a href="/MysqlTest/servlet/GetMysql?nubtn=<%=cugg-1%>"><%=cugg-1 %></a></li>
                    <li class="num"><a href="/MysqlTest/servlet/GetMysql?nubtn=<%=cugg %>"><%=cugg %></a></li>
                    <li class="num" ><a href="/MysqlTest/servlet/GetMysql?nubtn=<%=cugg+1%>"><%=cugg+1%></a></li>
                    <li class="num"><a href="/MysqlTest/servlet/GetMysql?nubtn=<%=cugg+2%>"><%=cugg+2%></a></li>
                    <li class="page-speciall">...</li><li class="num">34</li>
                    <li class="num"><a href="/MysqlTest/servlet/GetMysql?cupg=<%=currentPage+1%>" >下一页</a></li>
                    <li class="num"><a href=>尾页</a></li></ul>
              </div>
        </div>
    </div>