js：nodejs搭建http服务器为页面添加mysql中的数据

/**
 * 创建数据库连接，并获取数据
 */
var mysql = require(‘mysql‘);
//获取用户名，连接地址，密码，数据库名
function Db(host,user,pwd,port,database){
    this.host = host;
    this.user = user;
    this.pwd = pwd;
    this.port = port;
    this.database = database;
}
//获取数据
Db.prototype.excuteQuery = function(sql,connection,fun){
    connection.query(sql, function (error, rows) {
        var result="";
        if (error) {
            result = {
                "status": "500",
                "message": "服务器错误"
            }
        }else{
            result = {
                "status": "200",
                "message": "success",
                "data":rows
            }
        }
        fun(result);
    });
}
//建立连接
Db.prototype.getConnection = function(){
    var connection = mysql.createConnection({
        host: this.host,
        user: this.user,
        password:this.pwd,
        port: this.port,
        database: this.database
    });
    connection.connect();
    return  connection;
}
module.exports=Db;

/*数据分页*/
var Db=require(‘./db.js‘);
//创建一个新的数据库方法对象
var db=new Db(‘localhost‘,‘dyb‘,‘1743721550‘,‘3306‘,‘test‘);
var obj=null;
function Message(express) {
    //创建路由
    this.router = express.Router();
    this.execute();
}

//此函数检查该表中的数据条数
Message.prototype.count = function(sql,fun){
    var cSql  = "select count(*) from ("+sql+")";
    //通过对象调用函数创建连接
    var con=db.getConnection();
    //调用函数接收数据
    db.excuteQuery(cSql,con,function(data){
        fun(parseInt(data));
    })
}

//此函数通过linmit方法获取表中需要的数据
Message.prototype.limtModel = function(sql,start,pageSize,fun){
    //返回从start行开始，到pageSize中的数据
    var limitSql="select * from ("+sql+")aa limit "+start+","+pageSize;
    console.log(limitSql);
    var con=db.getConnection();
    db.excuteQuery(limitSql,con,function(data){
        fun(data.data)
    })
}
Message.prototype.execute = function(){
    var obj=this;
    //创建路由路径
    this.router.get("/message?",function(req,res){
        //初始从第几页开始
        var currentPage = 2;
        //每页显示的数据条数
        var pageSize = 5;
        var sql="select * from t_message where 1=1 order by s_date desc";
        //返回url中属性使currPafe的参数
        var cP=req.query.currPage;

        if(cP!=null&&(typeof cP)!=undefined){
            currentPage=cP;
        }
        obj.count(sql,function(count){
            //最大页数
            var maxPage=(count+pageSize-1)/pageSize;
            //如果此页大于最大页数，则吧最大页数赋给此页
            if(currentPage>maxPage){
                currentPage = maxPage;
            }
            //此页小于1则将此页置为一，从第一页开始显示
            if(currentPage<1){
                currentPage = 1;
            }
            /*
            * 第一个参数：sql:需要分页的数据
            * 第二个参数：通过当前的页数，和每页需要显示的数据条数，得出这一页数据开始是哪一条数据
            * 第三个参数：获得确定这页数据的最后一条数据是那一条数据
            * */

            var addr=req.protocol+"://"+ req.hostname+":3001/";
            obj.limtModel(sql,(currentPage-1)*pageSize,pageSize,function(data){
                res.render("qh/message",{args:data,cp:currentPage,addr:addr,last:maxPage});
            });
        })
    })
}

module.exports=Message;

<div class="mailbox mt20">

                   <%
                    args.forEach(function(row) {
                   %>
                        <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：<%=row.title%> </p>
                                <p class="name"><span>网友：<%=row.name%></span><span><%=row.s_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><%=row.s_des%></p>
                                </div>
                                <div class="answer">
                                    <p><strong>执法监察总队回复：</strong><%=row.l_des%></p>
                                </div>
                            </div>
                        </div>
                    <%
                        })
                    %>

              <div class="page">
                   <%
                      cp=parseInt(cp);
                   %>
                    <ul><li class="num"><a href=<%=addr%>message?cp=1>首页</a></li>
                        <li class="num"><a href=<%=addr%>message?cp=<%=cp-1%>>上一页</a></li>
                        <li class="num page-active">1</li>
                        <li class="num" >2</li>
                        <li class="num" >3</li>
                        <li class="num" >4</li>
                        <li class="num">5</li>
                        <li class="page-speciall">...</li><li class="num">34</li>
                        <li class="num"><a href=<%=addr%>message?cp=<%=cp+1%>>下一页</a></li>
                        <li class="num"><a href=<%=addr%>message?cp=<%=last%>>尾页</a></li></ul>
              </div>


            
        </div>