如何获取帖子以自定义帖子类型的给定字母开头？

Question

I am searching for a solution to get all posts of a custom post type for a while. I found a helpful answer here. But main problem using that snippet is, I want to get posts of a specific custom post type. Normal posts are blog posts so I want to filter those normal posts. I am not good with mysql so asking a solution.

Snippet to get all post of a given letter:

<?php
//get all post IDs for posts beginning with cap B, in title order,
//display posts
$first_char = 'B';

$postids=$wpdb->get_col($wpdb->prepare("
SELECT      ID
FROM        $wpdb->posts
WHERE       SUBSTR($wpdb->posts.post_title,1,1) = %s
ORDER BY    $wpdb->posts.post_title",$first_char)); 

if ($postids) {
$args=array(
  'post__in' => $postids,
  'post_type' => 'post',
  'post_status' => 'publish',
  'posts_per_page' => -1,
  'caller_get_posts'=> 1
);
$my_query = null;
$my_query = new WP_Query($args);
if( $my_query->have_posts() ) {
 echo 'List of Posts Titles beginning with the letter '. $first_char;
  while ($my_query->have_posts()) : $my_query->the_post(); ?>
    <p><a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title_attribute(); ?>"><?php the_title(); ?></a></p>
    <?php
  endwhile;
}
wp_reset_query();  // Restore global post data stomped by the_post().
}

?>

Answer 1

You can select your post type in:

$args=array(
  'post__in' => $postids,
  'post_type' => 'post',
  'post_status' => 'publish',
  'posts_per_page' => -1,
  'caller_get_posts'=> 1
);

by switching the "post_type" value to your custom post type ( not "post" as it is by default ).

for example:

'post_type' => 'customtype',