Wordpress Function For Getting Custom Posts IDs From Their URLs

Wordpress: Custom Post url_postid

<?php
/* Post URLs to IDs function, supports custom post types - borrowed and modified from url_to_postid() in wp-includes/rewrite.php */
function bwp_url_to_postid($url)
{
    global $wp_rewrite;
 
    $url = apply_filters('url_to_postid', $url);
 
    // First, check to see if there is a 'p=N' or 'page_id=N' to match against
    if ( preg_match('#[?&](p|page_id|attachment_id)=(\d+)#', $url, $values) )   {
        $id = absint($values[2]);
        if ( $id )
            return $id;
    }
 
    // Check to see if we are using rewrite rules
    $rewrite = $wp_rewrite->wp_rewrite_rules();
 
    // Not using rewrite rules, and 'p=N' and 'page_id=N' methods failed, so we're out of options
    if ( empty($rewrite) )
        return 0;
 
    // Get rid of the #anchor
    $url_split = explode('#', $url);
    $url = $url_split[0];
 
    // Get rid of URL ?query=string
    $url_split = explode('?', $url);
    $url = $url_split[0];
 
    // Add 'www.' if it is absent and should be there
    if ( false !== strpos(home_url(), '://www.') && false === strpos($url, '://www.') )
        $url = str_replace('://', '://www.', $url);
 
    // Strip 'www.' if it is present and shouldn't be
    if ( false === strpos(home_url(), '://www.') )
        $url = str_replace('://www.', '://', $url);
 
    // Strip 'index.php/' if we're not using path info permalinks
    if ( !$wp_rewrite->using_index_permalinks() )
        $url = str_replace('index.php/', '', $url);
 
    if ( false !== strpos($url, home_url()) ) {
        // Chop off http://domain.com
        $url = str_replace(home_url(), '', $url);
    } else {
        // Chop off /path/to/blog
        $home_path = parse_url(home_url());
        $home_path = isset( $home_path['path'] ) ? $home_path['path'] : '' ;
        $url = str_replace($home_path, '', $url);
    }
 
    // Trim leading and lagging slashes
    $url = trim($url, '/');
 
    $request = $url;
    // Look for matches.
    $request_match = $request;
    foreach ( (array)$rewrite as $match => $query) {
        // If the requesting file is the anchor of the match, prepend it
        // to the path info.
        if ( !empty($url) && ($url != $request) && (strpos($match, $url) === 0) )
            $request_match = $url . '/' . $request;
 
        if ( preg_match("!^$match!", $request_match, $matches) ) {
            // Got a match.
            // Trim the query of everything up to the '?'.
            $query = preg_replace("!^.+\?!", '', $query);
 
            // Substitute the substring matches into the query.
            $query = addslashes(WP_MatchesMapRegex::apply($query, $matches));
 
            // Filter out non-public query vars
            global $wp;
            parse_str($query, $query_vars);
            $query = array();
            foreach ( (array) $query_vars as $key => $value ) {
                if ( in_array($key, $wp->public_query_vars) )
                    $query[$key] = $value;
            }
 
        // Taken from class-wp.php
        foreach ( $GLOBALS['wp_post_types'] as $post_type => $t )
            if ( $t->query_var )
                $post_type_query_vars[$t->query_var] = $post_type;
 
        foreach ( $wp->public_query_vars as $wpvar ) {
            if ( isset( $wp->extra_query_vars[$wpvar] ) )
                $query[$wpvar] = $wp->extra_query_vars[$wpvar];
            elseif ( isset( $_POST[$wpvar] ) )
                $query[$wpvar] = $_POST[$wpvar];
            elseif ( isset( $_GET[$wpvar] ) )
                $query[$wpvar] = $_GET[$wpvar];
            elseif ( isset( $query_vars[$wpvar] ) )
                $query[$wpvar] = $query_vars[$wpvar];
 
            if ( !empty( $query[$wpvar] ) ) {
                if ( ! is_array( $query[$wpvar] ) ) {
                    $query[$wpvar] = (string) $query[$wpvar];
                } else {
                    foreach ( $query[$wpvar] as $vkey => $v ) {
                        if ( !is_object( $v ) ) {
                            $query[$wpvar][$vkey] = (string) $v;
                        }
                    }
                }
 
                if ( isset($post_type_query_vars[$wpvar] ) ) {
                    $query['post_type'] = $post_type_query_vars[$wpvar];
                    $query['name'] = $query[$wpvar];
                }
            }
        }
 
            // Do the query
            $query = new WP_Query($query);
            if ( !empty($query->posts) && $query->is_singular )
                return $query->post->ID;
            else
                return 0;
        }
    }
    return 0;
}
?>