PHP Simple Implementation Previous page next page Function Example _php tips

This article illustrates a simple PHP implementation of the previous page next page functionality. Share to everyone for your reference, specific as follows:

Idea Finishing:

Now a lot of people with ID 1 and minus 1 to achieve the previous and next, but the article ID will not be broken? So you need to know what the last ID and ID are OK.

So how to solve this problem, very simple!

Example:

If the ID200 of this article

<a href= "? action=up&id=200" > Previous </a>
<a href= "? action=down&id=200" > Next </a>

If you're implementing the previous article, write the function on the Action=up page.

$id = $_get[' id '];
Previous:
$sql = select * FROM article where ID < '. $id. ' ORDER BY id desc limit 0,1 ';
$rs = mysql_query ($sql);
$row = Mysql_fetch_array ($rs);
Next:
$sql = select * FROM article where ID < '. $id. ' ORDER BY ID ASC limit 0,1 ';
$rs = mysql_query ($sql);
$row = Mysql_fetch_array ($RS);

Principle, the query is smaller than the current ID (where ID < '. $id. ' Previous ' and 1 (limit 0,1) data larger than the current ID (where ID > '. $id. ' next), displayed in descending order (DESC, previous) and ascending (ASC, Next) , you can omit the descending or ascending order when you take only one article.

Specific implementation code: note the need to pass parameters

Front desk in the previous article, the next call:

<?php Echo Getprenext (Pre,news,$_request[catid],$_request[id]);? >//Display previous next function Getprenext ($gtype, $table, $catid, $id) {$preR =mysql_fetch_array (mysql_query ("select * from"). $ Table. "Where catid=". $catid. "And id< $id ORDER by id DESC limit 0,1");//id the most recent $nextR =mysql_fetch_array that is smaller than the incoming ID (MySQL  _query ("Select * from", $table. "Where catid=". $catid. "And id> $id ORDER by ID ASC limit 0,1");//id is the most recent one that is larger than the incoming ID $next = (Is_array ($nextR)?
  "Where id={$nextR [' ID ']}": ' Where 1>2 '); $pre = (Is_array ($preR)?
   "Where id={$preR [' ID ']}": ' Where 1>2 '); $query = "SELECT * from". $table. "
      ";
      $nextRow =mysql_query ($query. $next);
      $preRow = mysql_query ($query. $pre); if ($PreNext =mysql_fetch_array ($preRow)) {echo $PreNext [' pre '] = ' previous: <a href= ' newsshow.php?id= '. $preR [' ID ']." &&catid= ". $catid." ' > ". $PreNext [' title ']."
      </a> ";
      else {echo $PreNext [' pre '] = ' previous: no '; } if ($PreNext =mYsql_fetch_array ($nextRow)) {echo $PreNext [' next '] = ' Next: <a href= ' newsshow.php?id= '. $nextR [' id ']. " &&catid= ". $catid." ' > ". $PreNext [' title ']."
      </a> ";
      else {echo $PreNext [' next '] = "Next: No";

 }
}

Code is tested and available

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I hope this article will help you with the PHP program design.