主题：PHP分页类(超级经典)

<?php
class Page{
    private $PageSize = 10;
    private $TotalPage;
    private $RecordNum;
    private $NowPage;
    private $QueryString;
    private $IsEncode = false;
    private $IsNeedStat;
    private $CycNum = 5;    
public function __construct($sql,$CycNum = 5){
        if(!@mysql_ping()){
            echo "Please check your database link";
            exit;            
        }
        if(is_numeric($CycNum)){
            $this->CycNum = $CycNum;
        }else{
            $this->CycNum = $this->CycNum;
        }
        if(trim($sql) != ""){
            /*if(preg_match("/limit/",$sql)){
                list($sql,$limit)    =    explode("limit",$sql);
            }else{
                list($sql,$limit)    =    explode("LIMIT",$sql);
            }
            $this->QueryString = $sql;
            list($cnt1,$cnt2)    =    explode(",",$limit);
            if(!empty($cnt2)){
                $this->PageSize = $cnt2;
            }elseif(!empty($cnt1)){
                $this->PageSize = $cnt1;
            }else{
                $this->PageSize = $this->PageSize;
            }*/
            /**修改于2006年11月23日,解决出现Notice: Undefined offset: 2***/
            if(preg_match("/limit/",$sql)){
                list($sql,$limit)    =    explode("limit",$sql);
            }else if(preg_match("/LIMIT/",$sql)){
                list($sql,$limit)    =    explode("LIMIT",$sql);
            }
            //$this->QueryString = $sql;
            if(isset($limit)){
                list($cnt1,$cnt2)    =    explode(",",$limit);
                if(!empty($cnt2)){
                    $this->PageSize = $cnt2;
                }elseif(!empty($cnt1)){
                    $this->PageSize = $cnt1;
                }else{
                    $this->PageSize = $this->PageSize;
                }
            }
            $this->QueryString = $sql;
            unset($cnt1);
            unset($cnt2);
        }
    }
    /**
     *
     * @description 获取相应规定数目的记录
     * 并计算出总记录数，总页数等比较重要的参数
     * @param int $Sortid
     * 排序ID
     * @param bool $IsEncode
     * 页号是否加密，true为加密，false为不加密
     * @return string
     */
    public function StartPage($Sortid,$IsEncode = false,$IsNeedStat = false,$SortMethod = "down"){
        $Result = mysql_query($this->QueryString);
        $this->RecordNum = @mysql_num_rows($Result);
        $this->TotalPage = ceil($this->RecordNum/$this->PageSize);
        /*******************************************************
         * 初始化类属性IsNeedStat
         *******************************************************/
        if($IsNeedStat === true or $IsNeedStat === false){
            $this->IsNeedStat = $IsNeedStat;
        }else{
            echo "<b>Warning</b>:<i>方法StartPage中的参数IsNeedStat只能是bool</i>";
        }
        /*******************************************************
         * 初始化类属性IsEncode
         *******************************************************/
        if($IsEncode === true or $IsEncode === false){
            $this->IsEncode = $IsEncode;
        }else{
            echo "<b>Warning</b>:<i>方法StartPage中的参数IsEncode只能是bool</i>";
        }
        
        /*******************************************************
         *接收从url中传过来的当前页数,如果非数字，刚获取其整数值
         *******************************************************/
        if(isset($_REQUEST['NowPage'])){
            $this->NowPage = intval($_REQUEST['NowPage']);
        }
        
        /*******************************************************
         *根据$IsEncode的值来判断页号是否解密,如果$IsEncode的值非bool，
         *则给出警告信息,但并不影响程序执行，且默认不加密.
         *******************************************************/
        if($this->IsEncode === true){
          $this->NowPage = intval($this->StrDecode($_REQUEST['NowPage']));
        }
        //排列顺序 up 升序 down 降序
        if(isset($SortMethod) && $SortMethod == "up"){
            $SortMethod = "ASC";
        }elseif(isset($SortMethod) && $SortMethod == "down"){
            $SortMethod = "DESC";
        }else{
            echo "<b>Warning</b>:<i>方法StartPage中的参数SortMethod只能是down或者up</i>";
        }
        if(!isset($this->NowPage)){
            $this->NowPage = 1;
        }elseif($this->NowPage <= 0){
            $this->NowPage = 1;
        }elseif($this->NowPage > $this->TotalPage){
            $this->NowPage = $this->TotalPage;
        }else{
            $this->NowPage = $this->NowPage;
        }
        $OffSet = $this->PageSize * ($this->NowPage -1);
        $sql = $this->QueryString." ORDER BY ".$Sortid." ".$SortMethod." LIMIT ".$OffSet.",".$this->PageSize;
        return $sql;
    }
    /**
     *
     * @description
     * 翻页按扭的显示，如：首页 上页 下页 末页,可以定制自定义翻页按扭样式
     * 此函数也是 外面调用此类的入口.将返回经处理后的sql语
     * @param array $ButtonArray
     * 翻页按扭形式，用户可随意定制：如：
     * $ButtonArray = array("首页","上页","下页","末页");
     * @param string $JumpType
     * 附加选项，通过能参数，可定制跳转框，select 下拉跳转框，text 文
     * 本输入跳转框，none 不定制任何跳转框
     * @param bool $IsDisNum
     * 是否显示循环分页，true 显示 false 不显示;如：
     * 1 2 3 4 5 6 7 8 9 10
     * @return string
     */
    public function EndPage($ButtonArray,$JumpType = "none",$IsDisNum = false){
        $FirstPage = 1;
        $PrePage       = $this->NowPage - 1;
        $NextPage       = $this->NowPage + 1;
        $LastPage       = $this->TotalPage;
        /**
         * 根据参数$ButtomArray来得到用户定制的按扭，如果参数给出类型
         * 不正确，则采用系统默认按扭
         */
        if(!is_array($ButtonArray) or count($ButtonArray) != 4){
            $ButtonArray = array("First","Precede","Next","Last");
        }
        if($this->IsNeedStat === true){
            $ReturnStr   = "".$this->PageStat()."";
        }else{
            $ReturnStr   = "";    
        }        
        $ReturnStr  .= $this->ToPage($FirstPage,$ButtonArray[0],"First");
        $ReturnStr  .= " ";
        $ReturnStr  .= $this->ToPage($PrePage,$ButtonArray[1],"Pre");
        if($IsDisNum === true){
            $ReturnStr  .= " ".$this->DisPageNum()." ";
        }elseif($IsDisNum === false){
            $ReturnStr .= " ";
        }else{
            /**
             * 对参数的合法性，进行审核
             */
            echo ('<b>Warning</b>:<i>方法EndPage()中参数$IsDisNum的类型是bool,只能是 true或者false</i><br>');
            $ReturnStr .= " ";
        }
        $ReturnStr  .= $this->ToPage($NextPage,$ButtonArray[2],"Next");
        $ReturnStr  .= " ";
        $ReturnStr  .= $this->ToPage($LastPage,$ButtonArray[3],"Last");
        $ReturnStr  .= " ";
        if($JumpType === 'select'){
            $ReturnStr .= $this->JumpSelect('select');
        }elseif($JumpType === 'text'){
            $ReturnStr .= $this->JumpSelect('text');
        }elseif($JumpType === 'none'){
            //待写入
        }else{
            echo ('<b>Warning:</b><i>方法EndPage()中参数$JumpType 的值只能是 select text none </i><br>');
        }
        return $ReturnStr;
    }
    /**
     *
     * @description
     * 创建翻页按扭，并根据$Flag 的值来设置按扭是否可用，即：按
     * 扭是否带有链接,此此函数外界不可访问，属于该类私有方法
     * @param int $Page 将要跳转的页数
     * @param string $Msg 跳转按扭名称
     * @param string $Flag 按扭显示类型的判断
     * @return string
     */
private function ToPage($Page,$Msg,$Flag = ''){
        /*
         * 对$this->IsEncode为真，则对页数进行解密
         */
        if($this->IsEncode === true){
            $Page = $this->StrEncode($Page);
        }        
        $Url = $this->GetUrl($Page);
        $UrlStr = "<a id='pagelink' href='".$Url."' title='".$Msg."'>".$Msg."</a>";
        /*
         *如果当前页是小于或者等于第1页，那么首页和上页不显示链接
         * 如果当前页大于或者等于最后一页，那么末页和下页不显示链接
         * 对于其它情况，四个跳转按扭都显示*******
         */
        if(($this->NowPage <= 1 and ($Flag == "First" or $Flag == "Pre"))
        or ($this->NowPage >= $this->TotalPage and($Flag == "Next" or $Flag == "Last"))){
            $UrlStr = $Msg;
        }else{
            //$UrlStr="<a id='pagelink' href='#'>".$UrlStr."</a>";
              //$UrlStr = $Msg;
        }
        return $UrlStr;
    }
    /**
     *
     * @description
     * 获取当前的URL地址，并对将要跳转的地址做出修改,此方法也属于私有
     * 方法，外界不可访问，只能被类内部调用
     * @param int  $Page 将要跳转的页数
     * @return string
     */
    private function GetUrl($Page){
    /*下面代码于2006年12月1日进行了修改，其中$_SERVER['REMOTE_ADDR']被修改成下面的
     *$_SERVER['SERVER_ADDR'];$_SERVER['REMOTE_ADDR']为远程客户端地址，而$_SERVE
     *R['SERVER_ADDR']为服务器端地址SERVER_ADDR*/
        if($_SERVER['SERVER_PORT'] == 80){
            $Url = "http://".$_SERVER['SERVER_NAME'].$_SERVER['REQUEST_URI'];
        }else{
            $Url = "http://".$_SERVER['SERVER_NAME'].":".$_SERVER['SERVER_PORT'].$_SERVER['REQUEST_URI'];
        }
    //    $Url = preg_replace("/\?NowPage=[0-9]*&?/i","",$Url);
    //    $Url = preg_replace("/&NowPage = [0-9]*&?/i","",$Url);
        /*** *********************************************
         * 对url做出修改，将url中的?NowPage = "任何字符" 或者
         * $NowPage = "任何字符" 替换成 空，供下面对url的增加
         *************************************************/
        $Url = preg_replace("/\?NowPage=.*&?/i","",$Url);
        $Url = preg_replace("/&NowPage=.*&?/i","",$Url);
        /***************************************************
         *如果$Page = 0,则只取得当前URL,不再加向url全传值
         ***************************************************/
        if($Page === 0){
            return $Url;
        }
        /*判断先前是否已存在url传值，如果存在，
         *则加&NowPage=,否则加?/NowPage =
         */
        if(preg_match("/\?/",$Url)){
            $Url = $Url."&NowPage=".$Page;
        }else{
            $Url = $Url."?NowPage=".$Page;
        }
        
        return $Url;
    }
    /**
     *
     * @description
     * 对分页状况的一个统计，此方法可以定制，
     * 即：可要，也可不要，如需要显示当前状况
     * 在外部需显示的地方调用此方法即可.
     * @return string
     */
    public function PageStat(){
        $StatString  = "共有 ".$this->RecordNum." 条记录  ";
        $StatString .= "当前第 ".$this->NowPage." 页/共有 ".$this->TotalPage." 页 ";
        $StatString .= "每页显示 ".$this->PageSize." 条";
        return $StatString;
    }
    /**
     *
     * @description
     * 创建两种跳转框，一种下拉跳转菜单，一种文本输入菜单
     * 下拉菜单跳转框，当鼠标选中需跳转的页后，程序自动
     * 进行跳转到所指定的页数,文本输入菜单则是用户在文本
     * 框内输入要跳转的页数，鼠标外部单击，刚自己跳转
     * @param string $JumpType
     * 跳转菜单类型　select 下拉跳转框　text 文章输入跳转框，
     * none 不定制任何跳转框
     */
    private function JumpSelect($JumpType){
        $Url = $this->GetUrl(0);//获取当前url
        /**
         *判断先前是否被已经URL传值******
         */
        if(preg_match("/\?/",$Url)){
            $Url = $Url."&NowPage";
        }else{
            $Url = $Url."?NowPage";
        }
        $JumpString  = "转到";
        if($JumpType === 'select'){
            $JumpString .= "<select id='JumpSelect' name='NowPage' size='1'";
            $JumpString .= "onChange=\"window.location = '".$Url."='+this.value\">";
            for($i = 1; $i <= $this->TotalPage;$i++){
                /**选中当前页*/
                if($this->NowPage == $i){
                    $Extra = "selected";
                }else{
                $Extra = "";
                }
                if($this->IsEncode === true){
                    $JumpString .= "<option value='".$this->StrEncode($i)."' ".$Extra.">".$i."</option>";
                }else{
                    $JumpString .= "<option value='".$i."' ".$Extra.">".$i."</option>";
                }
            }
            $JumpString .= "</select> 页";
        }elseif($JumpType === 'text'){
            $Title = "鼠标外部单击，文章转向";
            $JumpString .= "<input id='JumpSelect' type='text' size='2' value='".$this->NowPage."'onBlur=\"";
            $JumpString .= "javascript:if(isNaN(parseInt(this.value)) || parseInt(this.value)";
            $JumpString .= " > ".$this->TotalPage."){alert('您输入的数字只能在 1 ～ ".$this->TotalPage;
            $JumpString .= "之间，请重新输入'); return false;}location.href='".$Url."='+parseInt(this.value)\" title='".$Title."'>";
            $JumpString .= " 页";
        }else{
            
        }
        return $JumpString;
    }
    /**
     *
     * @description 对页数进行循环显示，如 1 2 3 4 5
     * @return unknown
     */
    private function DisPageNum(){
        //循环显示规定数目的页号
        if(!isset($PageNumString)){
            $PageNumString = "";
        }
        for($i = $this->NowPage - $this->CycNum;$i < $this->NowPage + $this->CycNum;$i++){
            if($i <= 0){
                $i = 0;
                continue;
            }elseif($i > $this->TotalPage){
                break;
            }elseif($i == $this->NowPage){
                $PageNum = "<font color=green>[".$i."]</font>";
                $PageNumString .= $this->ToPage($i,$PageNum)." ";
            }else{
                $PageNumString .= $this->ToPage($i,$i)." ";
            }
        }
        return $PageNumString;
    }
    /**
     *
     * 对字符串进行加密
     * @param string $str
     * @return string
     */
    private function StrEncode($str){
        $encodeArr = str_split($str);
        $encode = '';
        for($i = 0; $i < count($encodeArr); $i++){
            $encodeStr = ord($encodeArr[$i]) + $i;
            $encode .= ($encodeStr)."|<<&>>|";
        }
        return urlencode(base64_encode(($encode)));
    }
    /**
     *
     * @description 对字符加密的字符串进行解密
     * @param string $str
     * @return string
     */
    private    function StrDecode($str){
        $decode = base64_decode(urldecode($str));
        $decodeArr = explode("|<<&>>|",$decode);
        $decodeStr = '';
         for($i = 0;$i < count($decodeArr);$i++){
             $decode = $decodeArr[$i];
             $decode = $decode;
             $decodeStr .= chr($decode - $i);
         }
         return $decodeStr;
    }
    /**
     *
     * @description
     * 本分页类的析构函数
     */
    public function __destruct(){
        //echo "destruct";
    }
}

$sql = "select id,title from 表名 imit 0,25";
      $page =  new Page($sql,5);
      $sql =  $page->StartPage("id",true,true,'down');
      $result = mysql_query($sql);
      while($arr = mysql_fetch_array($result)){
           echo $arr[1";
      }
  $ButtonArray = array("<","<<",">>",">");
      echo $page->EndPage($ButtonArray,"select",true);
  mysql_close($conn);
?>