所謂分頁顯示,也就是將數據庫中的結果集人為的分成一段一段的來顯示,這里需要兩個初始的參數: 每頁多少條記錄($PageSize)?
當前是第幾頁($CurrentPageID)?
現在只要再給我一個結果集,我就可以顯示某段特定的結果出來.
至于其他的參數,比如:上一頁($PReviousPageID)、下一頁($NextPageID)、總頁數($numPages)等等,都可以根據前邊這幾個東西得到.
以MySQL數據庫為例,如果要從表內截取某段內容,sql語句可以用:select * from table limit offset, rows.看看下面一組sql語句,嘗試一下發現其中的規率.
前10條記錄:select * from table limit 0,10
第11至20條記錄:select * from table limit 10,10
第21至30條記錄:select * from table limit 20,10
這一組sql語句其實就是當$PageSize=10的時候取表內每一頁數據的sql語句,我們可以總結出這樣一個模板:
select * from table limit ($CurrentPageID – 1) * $PageSize, $PageSize
拿這個模板代入對應的值和上邊那一組sql語句對照一下看看是不是那么回事.搞定了最重要的如何獲取數據的問題以后,剩下的就僅僅是傳遞參數,構造合適的sql語句然后使用php從數據庫內獲取數據并顯示了.以下我將用具體代碼加以說明.
3、簡單代碼
請詳細閱讀以下代碼,自己調試運行一次,最好把它修改一次,加上自己的功能,比如搜索等等.
實例代碼如下:
- <?php
- // 建立數據庫連接
- $link = mysql_connect(“localhost”, “mysql_user”, “mysql_passWord”)
- or die(“Could not connect: ” . mysql_error());
- // 獲取當前頁數
- if( isset($_GET['page']) ){
- $page = intval( $_GET['page'] );
- }
- else{
- $page = 1;
- }
- // 每頁數量
- $PageSize = 10;
- // 獲取總數據量
- $sql = “select count(*) as amount from table”;
- $result = mysql_query($sql);
- $row = mysql_fetch_row($result);
- $amount = $row['amount'];
- // 記算總共有多少頁
- if( $amount ){
- if( $amount < $page_size ){ $page_count = 1; } //如果總數據量小于$PageSize,那么只有一頁
- if( $amount % $page_size ){ //取總數據量除以每頁數的余數
- $page_count = (int)($amount / $page_size) + 1; //如果有余數,則頁數等于總數據量除以每頁數的結果取整再加一
- }else{
- $page_count = $amount / $page_size; //如果沒有余數,則頁數等于總數據量除以每頁數的結果
- }
- }
- else{
- $page_count = 0;
- }
- // 翻頁鏈接
- $page_string = ”;
- if( $page == 1 ){
- $page_string .= ‘第一頁|上一頁|’;
- }
- else{
- $page_string .= ‘<a href=?page=1>第一頁</a>|<a href=?page=’.($page-1).’>上一頁</a>|’;
- }
- if( ($page == $page_count) || ($page_count == 0) ){
- $page_string .= ‘下一頁|尾頁’;
- }
- else{
- $page_string .= ‘<a href=?page=’.($page+1).’>下一頁</a>|<a href=?page=’.$page_count.’>尾頁</a>’;
- }
- // 獲取數據,以二維數組格式返回結果
- if( $amount ){
- $sql = “select * from table order by id desc limit “. ($page-1)*$page_size .”, $page_size”;
- $result = mysql_query($sql);
- while ( $row = mysql_fetch_row($result) ){
- $rowset[] = $row;
- }
- }else{
- $rowset = array();
- }
- // 沒有包含顯示結果的代碼,那不在討論范圍,只要用foreach就可以很簡單的用得到的二維數組來顯示結果
- ?>
PHP分頁器制作,自動生成分面頁碼,JS調用函數
實例代碼如下:
- <?php
- class PageView{
- /**頁碼**/
- public $pageNo = 1;
- /**頁大小**/
- public $pageSize = 20;
- /**共多少頁**/
- public $pageCount = 0;
- /**總記錄數**/
- public $totalNum = 0;
- /**偏移量,當前頁起始行**/
- public $offSet = 0;
- /**每頁數據**/
- public $pageData = array();
- /**是否有上一頁**/
- public $hasPrePage = true;
- /**是否有下一頁**/
- public $hasNextPage = true;
- public $pageNoList = array();
- public $jsFunction ='jsFunction';
- /**
- *
- * @param unknown_type $count 總行數
- * @param unknown_type $size 分頁大小
- * @param unknown_type $string
- */
- public function __construct($count=0, $size=20,$pageNo=1,$pageData =array(),$jsFunction='jsFunction'){
- $this->totalNum = $count;//總記錄數
- $this->pageSize = $size;//每頁大小
- $this->pageNo = $pageNo;
- //計算總頁數
- $this->pageCount = ceil($this->totalNum/$this->pageSize);
- $this->pageCount = ($this->pageCount<=0)?1:$this->pageCount;
- //檢查pageNo
- $this->pageNo = $this->pageNo == 0 ? 1 : $this->pageNo;
- $this->pageNo = $this->pageNo > $this->pageCount? $this->pageCount : $this->pageNo;
- //計算偏移
- $this->offset = ( $this->pageNo - 1 ) * $this->pageSize;
- //計算是否有上一頁下一頁
- $this->hasPrePage = $this->pageNo == 1 ?false:true;
- $this->hasNextPage = $this->pageNo >= $this->pageCount ?false:true;
- $this->pageData = $pageData;
- $this->jsFunction = $jsFunction;
- }
- /**
- * 分頁算法
- * @return
- */
- private function generatePageList(){
- $pageList = array();
- if($this->pageCount <= 9){
- for($i=0;$i<$this->pageCount;$i++){
- array_push($pageList,$i+1);
- }
- }else{
- if($this->pageNo <= 4){
- for($i=0;$i<5;$i++){
- array_push($pageList,$i+1);
- }
- array_push($pageList,-1);
- array_push($pageList,$this->pageCount);
- }else if($this->pageNo > $this->pageCount - 4){
- array_push($pageList,1);
- array_push($pageList,-1);
- for($i=5;$i>0;$i--){
- array_push($pageList,$this->pageCount - $i+1);
- }
- }else if($this->pageNo > 4 && $this->pageNo <= $this->pageCount - 4){
- array_push($pageList,1);
- array_push($pageList,-1);
- array_push($pageList,$this->pageNo -2);
- array_push($pageList,$this->pageNo -1);
- array_push($pageList,$this->pageNo);
- array_push($pageList,$this->pageNo + 1);
- array_push($pageList,$this->pageNo + 2);
- array_push($pageList,-1);
- array_push($pageList,$this->pageCount);
- }
- }
- return $pageList;
- }
- /***
- * 創建分頁控件
- * @param
- * @return String
- */
- public function echoPageAsDiv(){
- $pageList = $this->generatePageList();
- $pageString ="<div class='pagination'><div class='page-bottom'>";
- if(!emptyempty($pageList)){
- if($this->pageCount >1){
- if($this->hasPrePage){
- $pageString = $pageString ."<a class='page-next' href="javascript:" .$this->jsFunction . "(" . ($this->pageNo-1) . ")">上一頁</a>";
- }
- foreach ($pageList as $k=>$p){
- if($this->pageNo == $p){
- $pageString = $pageString ."<span class='page-cur'>" . $this->pageNo . "</span>";
- continue;
- }
- if($p == -1){
- $pageString = $pageString ."<span class='page-break'>...</span>";
- continue;
- }
- $pageString = $pageString ."<a href="javascript:" .$this->jsFunction . "(" . $p . ")">" . $p . "</a>";
- }
- if($this->hasNextPage){
- $pageString = $pageString ."<a class='page-next' href="javascript:" .$this->jsFunction . "(" . ($this->pageNo+1) . ")">下一頁</a>";
- }
- }
- }
- $pageString = $pageString .("</div></div>");
- return $pageString;
- }
- }
- ?>
- <style type="text/css">
- <!--
- .pagination {font-family: Tahoma;overflow: hidden; padding-top: 12px; text-align: center;}
- .pagination-tab { margin-bottom: 20px;}
- .pagination a, .pagination .page-cur, .pagination .page-prev_g, .pagination .page-prev, .pagination .page-next, .pagination .page-next_g, .pagination .page-break, .pagination .page-skip {
- display: inline-block;font-family: Tahoma,SimSun,Arial; height: 22px;line-height:22px; margin: 0; min-width: 16px;padding: 0 5px; text-align: center; vertical-align: top; white-space: nowrap;}
- .pagination a, .pagination .page-prev_g, .pagination .page-prev, .pagination .page-next, .pagination .page-next_g, .pagination .page-cur, .pagination .page-break {
- border: 1px solid #ed3d83; color:#e9357d; font-weight:bold;}
- .pagination a:hover { border: 1px solid #ed3d83;text-decoration: none; background-color:#f95f9d; color:#fff;}
- .pagination .page-prev_g, .pagination .page-prev, .pagination .page-next, .pagination .page-next_g { width: 36px; background-image: url(../static/img/page.gif);}
- .pagination .page-prev { background-position: -0px -38px; padding-left: 16px;}
- .pagination .page-prev_g { background-position:0px -59px; padding-left: 16px; color:#cbcbcb; font-weight:normal;}
- .pagination .page-next { background-position: 0px 0px; padding-right: 16px; font-weight:normal;}
- .pagination .page-next_g { background-position: -0px -19px; padding-right: 16px; color:#cbcbcb;}
- .pagination .page-cur {background-color: #f95f9d; border: 1px solid #ed3d83;color: #fff;font-weight: bold;}
- .pagination .page-break {border: medium none; background:none transparent; color:#333;}
- -->
- </style>
PHP調用實例代碼如下:
- $pageNo = $_GET['pageNo'];
- if(emptyempty($pageNo)){
- }
- //分頁數據
- $pageData = News::getNewsPage($pageNo,$pageSize);
- //取得總行數
- $count = News::getNewsCount();
- //創建分頁器
- $p = new PageView($count['0']['TOTAL'],$pageSize,$pageNo,$pageData);
- //生成頁碼
- $pageViewString = $p->echoPageAsDiv();
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