Incorporating next/ previous in my 'foreach statement - php

Question

I want to have a previous|next link on my page to change pictures.
I use a function to get relevent elements. However, I do not know what additional code is require in my function and where to place it. Also what should be in the html section.
I have looked at many pages on next/previous from 'foreach' but I cannot seem to relate to them.
Code:
function image_data($image_album_id) {
$image_album__id = (int)$image_album_id;
$args = func_get_args();
unset($args[0]);
$fields = '`'.implode('`, `', $args).'`';
$query = mysql_query("SELECT $fields FROM `album_images`
WHERE `image_album_id`=$image_album_id AND `member_id`= '1'");
$ query_result = mysql_fetch_assoc($query);
foreach ($args as $field) {
$args[$field] = $query_result[$field];
}
return $args;
}
Html Page:
Last|
Next
</div>
<?php
$image_album_id =$_GET['image_album_id'];
$image_data = image_data($image_album_id, 'album_id', 'albumname', 'ext', 'timestamp');
echo '';
?>
<td class="smallfont albumthumb2" align="center" valign="middle" >
<img alt="" class="album_cover" src="<?php echo 'images/albums/thumbs/'. $image_data['album_id']. '/'. $image_album_id. '.' .$image_data['ext'];?> " height="175px" width="175px">
</td>
Many thanks. I hope I make sense.
Thanks for the speedy response.
Since there is a lot to look at and digest I thought I would just see if it works.
Alas no.
There is a parse error: syntax error, unexpected
'<' on line
$prev_link = Previous;
The only thing I notice within that section was an extra curly bracket after 'title="$prev_name"}'
I see there is the same for the 'title="$next_name"}'
WIth reference to your specific questions.
I get to the album_viewT page when I click on a link in a previous page. This contains tiny thumbnails. The link being localhost/Testing/album_view.php?artist_id=4&image_album_id=4 as an example.
Not sure if I fully understand "order of date is by image_album_data
Yes there are almost 3,000 rows in the database.
I should also mention that album_id has been replaced by artist_id.
Should the href be changed to "album_view.php/id/...

Answer 1

Your question lacks some data i.e. what is the page you are visiting that produces this code (the URL that is) and how is your data sorted. For instance I can see that you are providing potentially more information using the album_viewT.php? script but that is not necessarily the one that displays the HTML that you have produced.
So after all this I will make some assumptions and hopefully that will give you the right guidance to get to the solution.
I am assuming that your visiting page is http://mysite.com/albums/id/25
I am also assuming that the order of the data is by image_album_id.
Finally I am assuming that you have data in your db and I don't need to check whether there are returned data in the template for the current image. You will need to sort that out yourself.
You will need to get the data first from the database:
function image_data($image_album_id)
{
$results = array(
'previous' => FALSE,
'current' => FALSE,
'next' => FALSE,
);
$image_album__id = (int)$image_album_id;
$args = func_get_args();
unset($args[0]);
$fields = '`'.implode('`, `', $args).'`';
// Current record
$results['current'] = get_data(
$fields,
"AND image_album_id = {$image_album_id}"
);
// Previous - no need to run this if we don't have a current
if ($results['current'])
{
// Current record
$results['previous'] = get_data(
$fields,
"AND image_album_id < {$image_album_id} " .
"LIMIT 1"
);
}
// Next - no need to run this if we don't have a current
if ($results['current'])
{
// Current record
$results['next'] = get_data(
$fields,
"AND image_album_id > {$image_album_id} " .
"LIMIT 1"
);
}
// If all went well the $results array will contain the data
// for the 3 records. If we are at the beginning or the end,
// the previous and/or next will be FALSE
return $results;
}
function get_data($fields, $where = '')
{
$return = FALSE;
// Template
$template = "SELECT %s "
. "FROM album_images "
. "WHERE member_id = 1 %s";
// Current record
$sql = sprintf($template, $fields, $where);
$query = mysql_query($sql);
$query_result = mysql_fetch_assoc($query);
// If data has been found
if ($query_result)
{
$return = $query_result;
}
return $return;
}
For your HTML page:
<?php
$image_album_id = $_GET['image_album_id'];
$image_data = image_data(
$image_album_id,
'album_id', 'albumname', 'ext', 'timestamp'
);
$prev_link = '';
$next_link = '';
if ($image_data['previous'])
{
$prev_id = $image_data['previous']['album_id'];
$prev_name = $image_data['previous']['albumname'];
$prev_link = <a href="/albums/id/{$prev_id}" title="$prev_name"}>Previous</a>";
}
if ($image_data['next'])
{
$next_id = $image_data['next']['album_id'];
$next_name = $image_data['next']['albumname'];
$next_link = <a href="/albums/id/{$next_id}" title="$next_name"}>Next</a>";
}
$curr_id = $image_data['current']['album_id'];
$curr_ext = $image_data['current']['ext'];
?>
<?php echo $prev_link; ?>|<?php echo $next_link; ?>
</div>
<td class="smallfont albumthumb2" align="center" valign="middle">
<a href="album_viewT.php?images/albums/thumbs/
<?php echo "{$curr_id}/{$image_album_id}.{$curr_ext}; ?>
<img alt="" class="album_cover"
src="images/albums/thumbs/
<?php echo "{$curr_id}/{$image_album_id}.{$curr_ext}"; ?>
height="175px"
width="175px" />
</a>
</td>
Note: I have split the line for the img and a tags in the HTML file for clarity.