yii 學習筆記十六、數據分頁

一、如何分頁

總記錄行數 count，

每頁顯示 per，

分頁的總頁數 total_page = ceil(count/per)，向上取整

獲得具體每頁信息：limit 偏移量，條數

                 limit (page-1)*per, per

二、一個分頁類，yii組件component 文件名與類名在形式上要統一

compontents/Pagination.php

<?php
/**
 * 分頁類，以組件形式存在
 */
class Pagination {
        private $total; //數據表中總記錄數
        private $listRows; //每頁顯示行數
        private $limit;
        private $uri;
        private $pageNum; //頁數
        private $config=array('header'=>"個記錄", "prev"=>"上一頁", "next"=>"下一頁", "first"=>"首 頁", "last"=>"尾 頁");
        private $listNum=8;
        /*
         * $total
         * $listRows
         */
        public function __construct($total, $listRows=10, $pa=""){
            $this->total=$total;
            $this->listRows=$listRows;
            $this->uri=$this->getUri($pa);
            $this->page=!empty($_GET["page"]) ? $_GET["page"] : 1;
            $this->pageNum=ceil($this->total/$this->listRows);
            $this->limit=$this->setLimit();
        }
        private function setLimit(){
            return "Limit ".($this->page-1)*$this->listRows.", {$this->listRows}";
        }
        private function getUri($pa){
            $url=$_SERVER["REQUEST_URI"].(strpos($_SERVER["REQUEST_URI"], '?')?'':"?").$pa;
            $parse=parse_url($url);
                                                                    
            if(isset($parse["query"])){
                parse_str($parse['query'],$params);
                unset($params["page"]);
                $url=$parse['path'].'?'.http_build_query($params);
                                                                            
            }
            return $url;
        }
        function __get($args){
            if($args=="limit")
                return $this->limit;
            else
                return null;
        }
        private function start(){
            if($this->total==0)
                return 0;
            else
                return ($this->page-1)*$this->listRows+1;
        }
        private function end(){
            return min($this->page*$this->listRows,$this->total);
        }
        private function first(){
            if($this->page==1)
                $html.='';
            else
                $html.="&nbsp;&nbsp;<a href='{$this->uri}&page=1'>{$this->config["first"]}</a>&nbsp;&nbsp;";
            return $html;
        }
        private function prev(){
            if($this->page==1)
                $html.='';
            else
                $html.="&nbsp;&nbsp;<a href='{$this->uri}&page=".($this->page-1)."'>{$this->config["prev"]}</a>&nbsp;&nbsp;";
            return $html;
        }
        private function pageList(){
            $linkPage="";
                                                                        
            $inum=floor($this->listNum/2);
                                                                    
            for($i=$inum; $i>=1; $i--){
                $page=$this->page-$i;
                if($page<1)
                    continue;
                $linkPage.="&nbsp;<a href='{$this->uri}&page={$page}'>{$page}</a>&nbsp;";
            }
                                                                    
            $linkPage.="&nbsp;{$this->page}&nbsp;";
                                                                        
            for($i=1; $i<=$inum; $i++){
                $page=$this->page+$i;
                if($page<=$this->pageNum)
                    $linkPage.="&nbsp;<a href='{$this->uri}&page={$page}'>{$page}</a>&nbsp;";
                else
                    break;
            }
            return $linkPage;
        }
        private function next(){
            if($this->page==$this->pageNum)
                $html.='';
            else
                $html.="&nbsp;&nbsp;<a href='{$this->uri}&page=".($this->page+1)."'>{$this->config["next"]}</a>&nbsp;&nbsp;";
            return $html;
        }
        private function last(){
            if($this->page==$this->pageNum)
                $html.='';
            else
                $html.="&nbsp;&nbsp;<a href='{$this->uri}&page=".($this->pageNum)."'>{$this->config["last"]}</a>&nbsp;&nbsp;";
            return $html;
        }
        private function goPage(){
            return '&nbsp;&nbsp;<input type="text" onkeydown="javascript:if(event.keyCode==13){var page=(this.value>'.$this->pageNum.')?'.$this->pageNum.':this.value;location=\''.$this->uri.'&page=\'+page+\'\'}" value="'.$this->page.'" style="width:25px"><input type="button" value="GO"  page=(this.previousSibling.value>'.$this->pageNum.')?'.$this->pageNum.':this.previousSibling.value;location=\''.$this->uri.'&page=\'+page+\'\'">&nbsp;&nbsp;';
        }
        function fpage($display=array(0,1,2,3,4,5,6,7,8)){
            $html[0]="&nbsp;&nbsp;共有<b>{$this->total}</b>{$this->config["header"]}&nbsp;&nbsp;";
            $html[1]="&nbsp;&nbsp;每頁顯示<b>".($this->end()-$this->start()+1)."</b>條，本頁<b>{$this->start()}-{$this->end()}</b>條&nbsp;&nbsp;";
            $html[2]="&nbsp;&nbsp;<b>{$this->page}/{$this->pageNum}</b>頁&nbsp;&nbsp;";
                                                                        
            $html[3]=$this->first();
            $html[4]=$this->prev();
            $html[5]=$this->pageList();
            $html[6]=$this->next();
            $html[7]=$this->last();
            $html[8]=$this->goPage();
            $fpage='';
            foreach($display as $index){
                $fpage.=$html[$index];
            }
            return $fpage;
        }
                                                                
    }

三、分頁實現

1. 獲得總記錄數

2. 實例化分頁對象

3. 拼裝分頁sql

4. 獲得頁碼列表

/*
 * 建立一個測試方法，實現商品數據分頁顯示
 */
function actionShow1(){
    //獲得數據模型
    $goods_model = Goods::model();
              
    //1.獲得商品總的記錄數目
    $cnt = $goods_model -> count();
    $per = 6;
              
    //2. 實例化分頁類對象
    $page = new Pagination($cnt, $per);
              
    //3. 重新按照分頁的樣式拼裝sql語句進行查詢
    $sql = "select * from `goods` $page->limit";
    $goods_infos = $goods_model -> findAllBySql($sql);
              
    //4. 獲得分頁頁面列表(需要傳遞到視圖模板裏邊顯示)
    $page_list = $page->fpage(array(3,4,5,6,7));
              
              
    //調用視圖模板，給模板傳遞數據
    $this ->renderPartial('show',array('goods_infos'=>$goods_infos,'page_list'=>$page_list));
}

在 視圖中

echo $page_list

輸出分頁代碼