php 分享一个数据库分页类

<?php
    class page
    {
        private $pagesize;
        private $lastpage;
        private $totalpages;
        private $nums;
        private $numPage=1;

        function __construct($page_size,$total_nums)
        {
            $this->pagesize=$page_size;      //每页显示的数据条数
            $this->nums=$total_nums;     //总的数据条数
            $this->lastpage=ceil($this->nums/$this->pagesize);     //最后一页
            $this->totalpages=ceil($this->nums/$this->pagesize);   //总得分页数
            if(!empty($_GET[page]))
            {
                $this->numPage=$_GET[page];
                if(!is_int($this->numPage))  $this->numPage=(int)$this->numPage;
                if($this->numPage<1)  $this->numPage=1;
                if($this->numPage>$this->lastpage) $this->numPage=$this->lastpage;
            }
        }

        function show_page_result()
        {
            $row_num=(($this->numPage)-1) * $this->pagesize; //表示每一页从第几条数据开始显示
            $row_num=$row_num.",";
            $SQL="SELECT * FROM `test` LIMIT $row_num $this->pagesize";
            $db=new database();
            $query=$db->execute($SQL);
            while($row=mysql_fetch_array($query))
            {
                echo "<b>".$row[name]." | ".$row[sex]."<hr>";
            }
            $db=null;
        }

        function show_page_way_1()  //以"首页 上一页 下一页 尾页"形式显示
        {
            $url=$_SERVER["REQUEST_URI"];
            $url=parse_url($url);   //parse_url -- 解析 URL，返回其组成部分,注: 此函数对相对路径的 URL 不起作用。
            $url=$url[path];
            if($this->nums > $this->pagesize)      //判断是否满足分页条件
            {
                echo " 共 $this->totalpages 页 当前为第<font color=red><b>$this->numPage</b></font>页 共 $this->nums 条 每页显示 $this->pagesize 条";
                if($this->numPage==1)
                {
                    echo " 首页 ";
                    echo "上一页 ";
                }
                if($this->numPage >= 2 && $this->numPage <= $this->lastpage)
                {
                    echo " <a href=$url?page=1>首页</a> " ;
                    echo "<a href=$url?page=".($this->numPage-1).">上一页</a> " ;
                }

                if($this->numPage==$this->lastpage)
                {
                    echo "下一页 ";
                    echo "尾页<br>";
                }
                if($this->numPage >= 1 && $this->numPage < $this->lastpage)
                {
                    echo "<a href=$url?page=".($this->numPage+1).">下一页</a> ";
                    echo "<a href=$url?page=$this->lastpage>尾页</a><br> ";
                }
            }
            else    return;
        }

        function show_page_way_2()      //以数字形式显示"首页 1 2 3 4 尾页"
        {
            $url=$_SERVER["REQUEST_URI"];
            $url=parse_url($url);   //parse_url -- 解析 URL，返回其组成部分,注: 此函数对相对路径的 URL 不起作用。
            $url=$url[path];
            if($this->nums > $this->pagesize)
            {
                if($this->numPage==1)    echo "首页";
                else    echo "<a href=$url?page=1>首页</a>";
                for($i=1;$i<=$this->totalpages;$i++)
                {
                    if($this->numPage==$i)
                    {
                        echo " ".$i." ";
                    }
                    else
                    {
                        echo " <a href=$url?page=$i>$i</a> ";
                    }

                }
                if($this->numPage==$this->lastpage)       echo "尾页";
                else    echo "<a href=$url?page=$this->lastpage>尾页</a>";
            }
        }

        function show_page_way_3()
        {
            global $c_id;
            $url=$_SERVER["REQUEST_URI"];
            $url=parse_url($url);   //parse_url -- 解析 URL，返回其组成部分,注: 此函数对相对路径的 URL 不起作用。
            $url=$url[path];
            if($this->nums > $this->pagesize)      //判断是否满足分页条件
            {
                if($c_id)
                {
                    echo "到第<select name='select1' onChange=\\"location.href='$url?c_id=$c_id&page='+this.value+'&pagesize=$this->pagesize'\\">";
                }
                else    echo "到第<select name='select1' onChange=\\"location.href='$url?page='+this.value+'&pagesize=$this->pagesize'\\">";
                for($i = 1;$i <= $this->totalpages;$i++)
                echo "<option value='" . $i . "'" . (($this->numPage == $i) ? 'selected' : '') . ">" . $i . "</option>";
                echo "</select>页, 每页显示";
                if($c_id)
                {
                    echo "<select name=select2 onChange=\\"location.href='$url?c_id=$c_id&page=$this->numPage&pagesize='+this.value+''\\">";
                }
                else    echo "<select name=select2 onChange=\\"location.href='$url?page=$this->numPage&pagesize='+this.value+''\\">";
                for($i = 0;$i < 5;$i++) // 将个数定义为五种选择
                {
                    $choice= ($i+1)*4;
                    echo "<option value='" . $choice . "'" . (($this->pagesize == $choice) ? 'selected' : '') . ">" . $choice . "</option>";
                }
                echo "</select>个";
            }
            else    return;     //echo "没有下页了";

        }

    }

?>
//该片段来自于http://outofmemory.cn