Get image of a post in Wordpress - wordpress

Question

I want to make a slide show in wordpress, I made a category for it and now I want to get images of that category for my slide show. Here is part of my code:
<div id="slide-show">
<ul>
<?php query_posts('cat=1'); while(have_posts()): the_post();?>
<li>
<a href="<?php the_permalink();?>">
<img src="<?php
$image=wp_get_attachment_image_src(get_post_thumbnail_id($post->ID), 'thumbnail');
echo $image[0];?>" alt="<?php the_title();?>" /></a>
</li>
<?php endwhile; wp_reset_query();?>
</ul>
</div>
But it does not work. Can anybody help me please?

Answer 1

First of all, I'll repeat myself:
First of all, don't use query_posts.
Please, check:
When should you use WP_Query vs query_posts() vs get_posts()?
When to use WP_query(), query_posts() and pre_get_posts
In this case, I'd suggest building a function to create the desired output. You put it inside your theme functions.php file. Put it at the end of the file.
If there is any ?> as the last thing of a PHP file, remove it, it is not necessary and may break your site if there is any white space after it.
That said, our function will print exactly the Html you want and it is called like this in any theme template file (index.php, single.php, page.php, etc).
<?php get_gallery(4); ?>
The number 4 is the Category ID.
And this is the function, check the comments in the code:
function get_gallery( $id )
{
// Simple query
$posts = get_posts( array(
'category' => $id,
'post_status' => 'publish',
'post_type' => 'post',
) );
// Start building the Html code
$slide_show = '
<div id="slide-show">
<ul>';
// Iterate through the results
foreach ( $posts as $post )
{
// Assign value and test if it exists at the *same time*
if( $thumb = get_post_thumbnail_id( $post->ID ) )
{
$permalink = get_permalink( $post->ID );
$image = wp_get_attachment_image_src( $thumb );
// Build the Html elements
$slide_show .= '
<li>
<a href="' . $permalink . '">
<img src="'. $image[0] . '" alt="' . $post->post_title .'" />
</a>
</li>';
}
}
// Finish the Html
$slide_show .= '
</ul>
</div>
';
// Print the Html
echo $slide_show;
}
Result: