分頁自定義數據庫驅動的博客？

Question

最近我一直在用PHP來修補，並想製作自己的博客代碼。我知道如何從數據庫中進行選擇，在那裏我將有一個指定表格的表格。

我只想知道如何根據page GET變量只選擇表中的某些部分。

對不起，沒有任何代碼，但這是一個相當廣泛的問題，我覺得目前的代碼並不是真的有必要回答這個問題。

編輯：我正在使用MySQL。

Answer 1

使用MySQL，您可以使用LIMIT子句。假設你的頁面編號從1開始：

$pageSize = 10; 
$page = abs(intval($_GET["page"])); 
if ($page < 1) { 
    $page = 1; 
} 
$startResult = ($page - 1) * $pageSize; 
$sql = "SELECT * FROM `tableName` LIMIT $startResult, $pageSize"; 

一個非常重要的事情，從外部獲取參數時做（敵對）環境淨化你的投入。如果您不是惡意用戶或網絡機器人，可以在您的GET頁面變量中插入任何字符串並更改您的查詢。這被稱爲SQL注入。只是谷歌，你會發現很多的解釋。由於我們知道我們的頁面變量必須是一個正整數，因此我首先用intval（獲取一個變量的整數值），然後用abs（絕對值）處理它，因爲我們只需要正值。另一種方法是使用準備好的語句（尋找PDO）。

Answer 2

I will be like below. You have to do changes according to your code style 

<?php 
     /* 
      Place code to connect to your DB here. 
     */ 
     include('config.php'); // include your code to connect to DB. 

     $tbl_name="";  //your table name 
     // How many adjacent pages should be shown on each side? 
     $adjacents = 3; 

     /* 
      First get total number of rows in data table. 
      If you have a WHERE clause in your query, make sure you mirror it here. 
     */ 
     $query = "SELECT COUNT(*) as num FROM $tbl_name"; 
     $total_pages = mysql_fetch_array(mysql_query($query)); 
     $total_pages = $total_pages[num]; 

     /* Setup vars for query. */ 
     $targetpage = "filename.php"; //your file name (the name of this file) 
     $limit = 2;         //how many items to show per page 
     $page = $_GET['page']; 
     if($page) 
      $start = ($page - 1) * $limit;   //first item to display on this page 
     else 
      $start = 0;        //if no page var is given, set start to 0 

     /* Get data. */ 
     $sql = "SELECT column_name FROM $tbl_name LIMIT $start, $limit"; 
     $result = mysql_query($sql); 

     /* Setup page vars for display. */ 
     if ($page == 0) $page = 1;     //if no page var is given, default to 1. 
     $prev = $page - 1;       //previous page is page - 1 
     $next = $page + 1;       //next page is page + 1 
     $lastpage = ceil($total_pages/$limit);  //lastpage is = total pages/items per page, rounded up. 
     $lpm1 = $lastpage - 1;      //last page minus 1 

     /* 
      Now we apply our rules and draw the pagination object. 
      We're actually saving the code to a variable in case we want to draw it more than once. 
     */ 
     $pagination = ""; 
     if($lastpage > 1) 
     { 
      $pagination .= "<div class=\"pagination\">"; 
      //previous button 
      if ($page > 1) 
       $pagination.= "<a href=\"$targetpage?page=$prev\">« previous</a>"; 
      else 
       $pagination.= "<span class=\"disabled\">« previous</span>"; 

      //pages 
      if ($lastpage < 7 + ($adjacents * 2)) //not enough pages to bother breaking it up 
      { 
       for ($counter = 1; $counter <= $lastpage; $counter++) 
       { 
        if ($counter == $page) 
         $pagination.= "<span class=\"current\">$counter</span>"; 
        else 
         $pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";     
       } 
      } 
      elseif($lastpage > 5 + ($adjacents * 2)) //enough pages to hide some 
      { 
       //close to beginning; only hide later pages 
       if($page < 1 + ($adjacents * 2))   
       { 
        for ($counter = 1; $counter < 4 + ($adjacents * 2); $counter++) 
        { 
         if ($counter == $page) 
          $pagination.= "<span class=\"current\">$counter</span>"; 
         else 
          $pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";     
        } 
        $pagination.= "..."; 
        $pagination.= "<a href=\"$targetpage?page=$lpm1\">$lpm1</a>"; 
        $pagination.= "<a href=\"$targetpage?page=$lastpage\">$lastpage</a>";  
       } 
       //in middle; hide some front and some back 
       elseif($lastpage - ($adjacents * 2) > $page && $page > ($adjacents * 2)) 
       { 
        $pagination.= "<a href=\"$targetpage?page=1\">1</a>"; 
        $pagination.= "<a href=\"$targetpage?page=2\">2</a>"; 
        $pagination.= "..."; 
        for ($counter = $page - $adjacents; $counter <= $page + $adjacents; $counter++) 
        { 
         if ($counter == $page) 
          $pagination.= "<span class=\"current\">$counter</span>"; 
         else 
          $pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";     
        } 
        $pagination.= "..."; 
        $pagination.= "<a href=\"$targetpage?page=$lpm1\">$lpm1</a>"; 
        $pagination.= "<a href=\"$targetpage?page=$lastpage\">$lastpage</a>";  
       } 
       //close to end; only hide early pages 
       else 
       { 
        $pagination.= "<a href=\"$targetpage?page=1\">1</a>"; 
        $pagination.= "<a href=\"$targetpage?page=2\">2</a>"; 
        $pagination.= "..."; 
        for ($counter = $lastpage - (2 + ($adjacents * 2)); $counter <= $lastpage; $counter++) 
        { 
         if ($counter == $page) 
          $pagination.= "<span class=\"current\">$counter</span>"; 
         else 
          $pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";     
        } 
       } 
      } 

      //next button 
      if ($page < $counter - 1) 
       $pagination.= "<a href=\"$targetpage?page=$next\">next »</a>"; 
      else 
       $pagination.= "<span class=\"disabled\">next »</span>"; 
      $pagination.= "</div>\n";  
     } 
    ?> 

     <?php 
      while($row = mysql_fetch_array($result)) 
      { 

      // Your while loop here 

      } 
     ?> 

    <?=$pagination?> 


Please make changes according to your code style 

Answer 3

請根據需要進行更改。您可以輕鬆設計頁面導航的外觀。

<?php 
if(!empty($_GET["start"])){ 
    $start = $_GET['start'];// To take care global variable if OFF 
}else{ 
    $start = 0; 
} 
if(!($start > 0)) { // This variable is set to zero for the first page 
    $start = 0; 
} 

$eu = ($start - 0); 
$limit   = 5; // No of records to be shown per page. 
$whathis  = $eu + $limit; 
$back   = $eu - $limit; 
$next   = $eu + $limit; 

// to check the total number of records 
$query   = mysql_query(" SELECT * FROM <tablename> ") or die (mysql_error()); 
$total_rows  = mysql_num_rows($query); 

//select the record with limitation 
$query   = mysql_query(" SELECT * FROM <tablename> limit $eu, $limit ") or die (mysql_error()); 

//code for previous 
if($back >=0) { 
echo "<a href='yourpage.php?start=$back'><font face='Verdana' size='2'>PREV</font></a>&nbsp;&nbsp;"; 
} 

//code for the number of page with links 
$i  = 0; 
$x = 1; 
for($i=0;$i < $total_rows;$i=$i+$limit){ 
if($i != $eu){ 
    echo "<a href='yourpage.php?start=$i'><font face='Verdana' size='2'>$x</font></a> "; 
}else { 
    echo "<font face='Verdana' size='4' color=red>$x</font>"; 
} // Current page is not displayed as link and given font color red 

$x = $x+1; 
} 
//code for next 
if($whathis < $total_rows) { 
echo "<a href='yourpage.php?start=$next'><font face='Verdana' size='2'>NEXT</font></a>"; 
}  
?>