Pagination Help

goosehunter

I am trying to add a pagination feature to an existing script that works well without the pagination. I have copied a pagination example and could make it work as a separate document. But when I try to include the pagination to script that allows a user modified query, the links do not work when clicked. I suspect the form action should call yet another script instead of the same, burgresults.php script. Here is the code that does not produce functioning links.

<html>
<head>
<title>Product Search Results</title>
</head>
<body>

<form action="burgresults.php" method="post">
Choose Search Type:<br />
<select name="searchtype">
<option value="model">Model</option>
<option value="description">Description</option>
<option value="category">Category</option>
<option value="make">Make</option>
</select>
<br />
Enter Search Term:<br />
<input name="searchterm" type="text">
<br />
<input type="submit" value="Search">
</form>

<h1>Product Search Results</h1>

PHP:

<?php
$searchtype=$HTTP_POST_VARS['searchtype'];
$searchterm=$HTTP_POST_VARS['searchterm'];

$searchterm= trim($searchterm);

if (!$searchtype || !$searchterm)
{
echo 'You have not entered search details. Please go back and try again.';
//exit;
}

$searchtype = addslashes($searchtype);
$searchterm = addslashes($searchterm);

$db = mysql_pconnect('localhost', 'burgsurfer', 'ham789');

if (!$db)
{
echo 'Error: Could not connect to database. Please try again later.';
exit;
}

mysql_select_db('burgweb');
$query = "select * from products where ".$searchtype." like '%".$searchterm."%'";
$result = mysql_query($query);

$num_results = mysql_num_rows($result);

echo '<p>Number of products found: '.$num_results.'</p>';

if (!($limit)){
$limit = 10;} // Default results per-page.
if (!($page)){
$page = 0;} // Default page value.
$numrows = $num_results;
if ($numrows == 0){
echo("No results found matching your query - $query");
exit();}

$pages = intval($numrows/$limit); // Number of results pages.

if ($numrows%$limit) {
$pages++;} // has remainder so add one page

$current = ($page/$limit) + 1; // Current page number.

if (($pages < 1) || ($pages == 0)) {
$total = 1;} // If $pages is less than one or equal to 0, total pages is 1.

else {
$total = $pages;} // Else total pages is $pages value.

$first = $page + 1; // The first result.

if (!((($page + $limit) / $limit) >= $pages) && $pages != 1) {
$last = $page + $limit;} //If not last results page, last result equals $page plus $limit.

else{
$last = $numrows;} // If last results page, last result equals total number of results.

$query = "select * from products where ".$searchtype." like '%".$searchterm."%' limit $page, $limit";
$result = mysql_query($query);

for ($i=0; $i <$limit; $i++)

{
$row = mysql_fetch_array($result);
echo '<p><strong>'.($i+1).'. Model: ';
echo htmlspecialchars(stripslashes($row['model']));
echo '</strong><br />Description: ';
echo stripslashes($row['description']);
echo '<br />Price: ';
echo stripslashes($row['price']);
echo '<br />Category: ';
echo stripslashes($row['category']);
echo '<br />Make: ';
echo stripslashes($row['make']);
echo '<br />Weight: ';
echo stripslashes($row['weight']);
echo '<br />Age: ';
echo stripslashes($row['age']);
echo '<br />Availibilty: ';
if (stripslashes($row['number']) > 0)
{
echo 'In Stock';
}
else
{
echo 'Sold Out';
}
echo '</p>';
}
?>

PHP:

<php?
if ($page != 0) { // Don't show back link if current page is first page.
$back_page = $page - $limit;
echo("<a href=\"$PHP_SELF?query=$query&page=$back_page&limit=$limit\">back</a>\n");}

for ($i=1; $i <= $pages; $i++) // loop through each page and give link to it.
{
$ppage = $limit*($i - 1);
if ($ppage == $page){
echo("<b>$i</b> \n");} // If current page don't give link, just text.
else{
echo("<a href=\"$PHP_SELF?query=$query&page=$ppage&limit=$limit\">$i</a>\n");}
}

if (!((($page+$limit) / $limit) >= $pages) && $pages != 1) { // If last page don't give next link.
$next_page = $page + $limit;
echo("<a href=\"$PHP_SELF?query=$query&page=$next_page&limit=$limit\">next</a>\n");}
?>

</p>

</body>
</html>

planetsim

As nice as some people are here if you want some help please wrap your code in [php][/php]

goosehunter

Thank you for pointing out that I had neglected the PHP tags to identify code sections. I'm new to this forum and it shows. I have edited the orginal post and manually entered "PHP:" and underscore lines to segment this code. Are you requesting I use the vB code instead? I'll try a second posting with the vB and PHP option enabled so I can see how that works.

goosehunter

Let's see if this will format the PHP code in colors.

<html>
<head>
<title>Product Search Results</title>
</head>
<body>

<h1>Product Search Results</h1>

<?php
  $searchtype=$HTTP_POST_VARS['searchtype'];
  $searchterm=$HTTP_POST_VARS['searchterm'];

  $searchterm= trim($searchterm);

  if (!$searchtype || !$searchterm)
  {
     echo 'You have not entered search details.  Please go back and try again.';
     //exit;
  }

  $searchtype = addslashes($searchtype);
  $searchterm = addslashes($searchterm);

  $db = mysql_pconnect('localhost', 'burgsurfer', 'ham789');

  if (!$db)
  {
     echo 'Error: Could not connect to database.  Please try again later.';
     exit;
  }

  mysql_select_db('burgweb');
  $query = "select * from products where ".$searchtype." like '%".$searchterm."%'";
  $result = mysql_query($query);

  $num_results = mysql_num_rows($result);

  echo '<p>Number of products found: '.$num_results.'</p>';


if (!($limit)){
$limit = 10;} // Default results per-page.
if (!($page)){
$page = 0;} // Default page value.
$numrows = $num_results;
if ($numrows == 0){
echo("No results found matching your query - $query");
exit();}

$pages = intval($numrows/$limit); // Number of results pages.

if ($numrows%$limit) {
$pages++;} // has remainder so add one page

$current = ($page/$limit) + 1; // Current page number.

if (($pages < 1) || ($pages == 0)) {
$total = 1;} // If $pages is less than one or equal to 0, total pages is 1.

else {
$total = $pages;} // Else total pages is $pages value.

$first = $page + 1; // The first result.

if (!((($page + $limit) / $limit) >= $pages) && $pages != 1) {
$last = $page + $limit;} //If not last results page, last result equals $page plus $limit.

else{
$last = $numrows;} // If last results page, last result equals total number of results.

$query = "select * from products where ".$searchtype." like '%".$searchterm."%' limit $page, $limit";
$result = mysql_query($query);

  for ($i=0; $i <$limit; $i++)

  {
     $row = mysql_fetch_array($result);
     echo '<p><strong>'.($i+1).'. Model: ';
     echo htmlspecialchars(stripslashes($row['model']));
     echo '</strong><br />Description: ';
     echo stripslashes($row['description']);
     echo '<br />Price: ';
     echo stripslashes($row['price']);
     echo '<br />Category: ';
     echo stripslashes($row['category']);
     echo '<br />Make: ';
     echo stripslashes($row['make']);
     echo '<br />Weight: ';
     echo stripslashes($row['weight']);
     echo '<br />Age: ';
     echo stripslashes($row['age']);
     echo '<br />Availibilty: ';
     if (stripslashes($row['number']) > 0)
     	{
     		echo 'In Stock';
     	}
     else
     	{
     		echo 'Sold Out';
     	}
     echo '</p>';
  }
?>

<php?
if ($page != 0) { // Don't show back link if current page is first page.
$back_page = $page - $limit;
echo("<a href=\"$PHP_SELF?query=$query&page=$back_page&limit=$limit\">back</a>\n");}

for ($i=1; $i <= $pages; $i++) // loop through each page and give link to it.
{
 $ppage = $limit*($i - 1);
 if ($ppage == $page){
 echo("<b>$i</b> \n");} // If current page don't give link, just text.
 else{
 echo("<a href=\"$PHP_SELF?query=$query&page=$ppage&limit=$limit\">$i</a>\n");}
}

if (!((($page+$limit) / $limit) >= $pages) && $pages != 1) { // If last page don't give next link.
$next_page = $page + $limit;
echo("<a href=\"$PHP_SELF?query=$query&page=$next_page&limit=$limit\">next</a>\n");}
?>

</p>

</body>
</html>

goosehunter

If I understand what is happening, the "$PHP_SELF" causes the page script to run again. The following URL link generation code causes the burgresults.php to reload which resets the $searchterm variable to empty.

 
echo("<a href=\"$PHP_SELF?query=$query&page=$ppage&limit=$limit\">$i</a>\n");}

This produces the following URL, minus the local directory for brevity:

../burgresults.php?query=select%20*%20from%20products%20where%20model%20like%20'%756%25'%20limit%200,%2010&page=10&limit=10

And since it is trying to run the query with an empty variable when clicking a link, the following error message appears:

You have not entered search details. Please go back and try again.//My error message for missing search criteria.

Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in ../burgresults.php on line 55

Number of products found:
No results found matching your query - select * from products where like '%%'

All of the examples I've seen on-line do not include form elements/variables that get wipped out when the page reloads from the "$PHP_SELF" part of the URL.

It seems the solution might be to create another php file that does not contain the form elements and call that code to process the URL. And pass the variable values within the URL. I have tried doing this but am not having the desired result.

goosehunter

Another forum supplied the clue I needed to solve this problem which was to remove the query portion for the URL.

echo("<a href=\"$PHP_SELF?searchtype=$searchtype&searchterm=$searchterm&page=$ppage&limit=$limit\">$i</a>\n");

Now my next challenge is to provide a limit to the results where the last page should show less than the limit quantity. Currently, my for loop has a limit of 10 and if the last page should only show 4, it continues to try and display labels for 6 more items without any data for those 6.

for ($i=0; $i <$limit; $i++)  

  {
     $row = mysql_fetch_array($result);
     echo '<p><strong>Model: ';
     echo htmlspecialchars(stripslashes($row['model']));
     echo '</strong><br />Description: ';
     echo stripslashes($row['description']);
     echo '<br />Price: ';
     echo stripslashes($row['price']);
     echo '<br />Category: ';
     echo stripslashes($row['category']);
     echo '<br />Make: ';
     echo stripslashes($row['make']);
     echo '<br />Weight: ';
     echo stripslashes($row['weight']);
     echo '<br />Age: ';
     echo stripslashes($row['age']);
     echo '<br />Availibilty: ';
     if (stripslashes($row['number']) > 0)
     	{
     		echo 'In Stock';
     	}
     else
     	{
     		echo 'Sold Out';
     	}
     echo '</p>';
  }

Is there a way to use WHILE with a LIMIT argument or yet some other way to accomplish this goal?

goosehunter

With a query result of 24 items and a limit of 10, the following produces 10 items on the 1st page, 10 items on the 2nd, and 4 items on the 3rd. But clicking on the 3rd page link causes 3 URL links [1 2 3] to change to 6 URL links [1 2 3 4 5 6] because the limit is changed to the remainder amount. How can I control the proper generation of these links and still have the correct page results?

for ($i=0; $i <$limit; $i++)
    {
     $row = mysql_fetch_array($result);
     echo '<p><strong>'.($i+1).'. Model: ';
     echo htmlspecialchars(stripslashes($row['model']));
     echo '</strong><br />Description: ';
     echo stripslashes($row['description']);
     echo '<br />Price: ';
     echo stripslashes($row['price']);
     echo '<br />Category: ';
     echo stripslashes($row['category']);
     echo '<br />Make: ';
     echo stripslashes($row['make']);
     echo '<br />Weight: ';
     echo stripslashes($row['weight']);
     echo '<br />Age: ';
     echo stripslashes($row['age']);
     echo '<br />Availibilty: ';
     if (stripslashes($row['number']) > 0)
     	{
     		echo 'In Stock';
     	}
     else
     	{
     		echo 'Sold Out';
     	}
     echo '</p>';
  }
?>

<p align="center">
<?
if ($page != 0) { // Don't show back link if current page is first page.
$back_page = $page - $limit;
echo("<a href=\"$PHP_SELF?searchtype=$searchtype&searchterm=$searchterm&page=$back_page&limit=$limit\">back</a>\n");}
$limit = $storelimit;
if ($numrows%$limit) { //if remainer amount change limit for last page
for ($i=1; $i <= $pages-1; $i++) // loop through each page and give link to it.
{
 $ppage = $limit*($i - 1);
 if ($ppage == $page){
 echo("<b>$i</b> \n");} // If current page don't give link, just text.
 else{
 echo("<a href=\"$PHP_SELF?searchtype=$searchtype&searchterm=$searchterm&page=$ppage&limit=$limit\">$i</a>\n");}
}
$limit = $numrows%$limit;
echo("<a href=\"$PHP_SELF?searchtype=$searchtype&searchterm=$searchterm&page=$ppage&limit=$limit\">$i</a>\n");
$limit = $storelimit;

}else {
if ($numrows%$limit) {
exit;
}
for ($i=1; $i <= $pages; $i++) // loop through each page and give link to it.
{
 $ppage = $limit*($i - 1);
 if ($ppage == $page){
 echo("<b>$i</b> \n");} // If current page don't give link, just text.
 else{
 echo("<a href=\"$PHP_SELF?searchtype=$searchtype&searchterm=$searchterm&page=$ppage&limit=$limit\">$i</a>\n");}
}
}

if (!((($page+$limit) / $limit) >= $pages) && $pages != 1) { // If last page don't give next link.
$next_page = $page + $limit;
echo("<a href=\"$PHP_SELF?searchtype=$searchtype&searchterm=$searchterm&page=$next_page&limit=$limit\">next</a>\n");}
?>