您的src;
<img src="http://example.com//wp-admin/admin-ajax.php?action=random_banner">
试试这个：
<img src="http://example.com/wp-admin/admin-ajax.php?action=random_banner">
或
<img src="<?php echo admin_url( \'admin-ajax.php?action=random_banner\' ); ?>">
您还可以使用查询获取随机图像。
阿贾克斯
add_action( \'wp_ajax_random_banner\', \'random_banner\' );
add_action( \'wp_ajax_nopriv_random_banner\', \'random_banner\' );
function random_banner() {
// search for 1 random image
$image_ids = get_posts(
array(
\'post_type\' => \'attachment\',
\'post_mime_type\' => \'image\',
\'post_status\' => \'inherit\',
\'numberposts\' => 1,
\'orderby\' => \'rand\',
\'fields\' => \'ids\',
) );
// convert id to url
$images = array_map( "wp_get_attachment_url", $image_ids );
$image_id = $image_ids[ 0 ];
$image_url = $images[0];
// make sure path is readable -- if not, stop!
// this won\'t work with URL :(
// if( !is_readable($image_url)) {
// wp_die( "File is not readable: $image_url" );
// }
$image = file_get_contents( $image_url );
$type = get_post_mime_type( $image_id );
if ( empty ( $type ) ) {
$type = "image/jpg";
}
// output headers and image data
nocache_headers();
header( "Content-type: $type;" );
header( "Content-Length: " . strlen( $image ) );
echo $image;
die();
}
更新| Endpoint Alternate跳过AJAX调用，只需使用
add_rewrite_rule().
IMAGE
<img src="http://example.com/api/images/random">
PHP
/**
* Creates endpoint to select random image from Library
*
* http://example.com/api/images/random
*
*/
if ( ! class_exists( \'Endpoint_RandomImage\' ) ):
/**
* The code that registers the endpoint and handles the result
*/
class Endpoint_RandomImage {
const ENDPOINT_NAME = \'api/images/random\'; // endpoint to capture
const ENDPOINT_QUERY_NAME = \'__api_images_random\'; // turns to param
// WordPress hooks
public function run() {
add_filter( \'query_vars\', array( $this, \'add_query_vars\' ), 0 );
add_action( \'parse_request\', array( $this, \'sniff_requests\' ), 0 );
add_action( \'init\', array( $this, \'add_endpoint\' ), 0 );
}
// Add public query vars
public function add_query_vars( $vars ) {
$vars[] = static::ENDPOINT_QUERY_NAME;
$vars[] = \'extra\';
return $vars;
}
// Add API Endpoint
public function add_endpoint() {
add_rewrite_rule( \'^\' . static::ENDPOINT_NAME . \'?$\', \'index.php?\' . static::ENDPOINT_QUERY_NAME . \'=1\', \'top\' );
add_rewrite_rule( \'^\' . static::ENDPOINT_NAME . \'/([^/]+)/?$\', \'index.php?\' . static::ENDPOINT_QUERY_NAME . \'=1&extra=$matches[1]\', \'top\' );
// --->
flush_rewrite_rules( true ); //// <---------- REMOVE THIS WHEN DONE TESTING
// --->
}
// Sniff Requests
public function sniff_requests( $wp_query ) {
global $wp;
if ( isset( $wp->query_vars[ static::ENDPOINT_QUERY_NAME ] ) ) {
$this->handle_request(); // handle it
}
}
// Handle Requests
protected function handle_request() {
global $wp;
$image_ids = get_posts(
array(
\'post_type\' => \'attachment\',
\'post_mime_type\' => \'image\',
\'post_status\' => \'inherit\',
\'numberposts\' => 1,
\'orderby\' => \'rand\',
\'fields\' => \'ids\',
) );
// convert ids to urls
// $images = array_map( "wp_get_attachment_url", $image_ids );
// convert ids to paths
$images = array_map( "get_attached_file", $image_ids );
$image_id = $image_ids[ 0 ];
$image_path = $images[ 0 ];
// make sure url is readable -- if not, stop!
if ( ! is_readable( $image_path ) ) {
wp_die( "File is not readable: $image_path" );
}
$image = file_get_contents( $image_path );
$type = get_post_mime_type( $image_id );
if ( empty ( $type ) ) {
$type = "image/jpg";
}
// output headers and image data
nocache_headers();
header( "Content-type: $type;" );
header( "Content-Length: " . strlen( $image ) );
echo $image;
die();
}
}
$ep = new Endpoint_RandomImage();
$ep->run();
endif; // Endpoint_RandomImage
端点备用#2
<img src="http://example.com/api/random-banner/">
使用“重写+查询”标记。
<?php
if ( ! class_exists( \'Prefix_API\' ) ) {
class Prefix_API {
function __invoke() {
add_action( \'init\', array ( $this, \'prefix__init\' ) );
add_action( \'pre_get_posts\', array ( $this, \'prefix__pre_get_posts\' ) );
}
/**
* Register a rewrite endpoint for the API.
*/
function prefix__init() {
// add tags with `_` prefix to avoid screwing up query
add_rewrite_tag( \'%_api_action%\', \'([a-zA-Z\\d\\-_+]+)\' );
// create URL rewrite
add_rewrite_rule( \'^api/([a-zA-Z\\d\\-_+]+)/?\', \'index.php?_api_action=$matches[1]\', \'top\' );
// required once after rules added/changed
flush_rewrite_rules( true );
}
/**
* Handle data (maybe) passed to the API endpoint.
*
* @param $query
*/
function prefix__pre_get_posts( $query ) {
if ( isset( $query->query_vars[ \'_api_action\' ] ) ) {
switch ( $query->query_vars[ \'_api_action\' ] ) {
case \'random-banner\';
$this->prefix__show_random_image();
break;
}
// kill the request on an API action call
die();
}
}
/**
* Show random image
*
* @see http://example.com/api/random-banner/
*/
function prefix__show_random_image() {
$image_ids = get_posts( array (
\'post_type\' => \'attachment\',
\'post_mime_type\' => \'image\',
\'post_status\' => \'inherit\',
\'numberposts\' => 1,
\'orderby\' => \'rand\',
\'fields\' => \'ids\',
) );
// convert ids to urls
// $images = array_map( "wp_get_attachment_url", $image_ids );
// convert ids to paths
$images = array_map( "get_attached_file", $image_ids );
$image_id = $image_ids[ 0 ];
$image_path = $images[ 0 ];
// make sure url is readable -- if not, stop!
if ( ! is_readable( $image_path ) ) {
wp_die( "File is not readable: $image_path" );
}
$image = file_get_contents( $image_path );
$type = get_post_mime_type( $image_id );
if ( empty ( $type ) ) {
$type = "image/jpg";
}
// output headers and image data
nocache_headers();
header( "Content-type: $type;" );
header( "Content-Length: " . strlen( $image ) );
echo $image;
die();
}
}
// create api instance
$api = new Prefix_API();
// initialize the api hooks
$api();
}
REST API
<img src="http://example.com/wp-json/prefix/v1/random-image/">
此版本使用
custom REST API route.
/**
* Register the REST route.
*
* @see http://example.com/wp-json/prefix/v1/random-image/
*/
add_action( \'rest_api_init\', function () {
register_rest_route( \'prefix/v1\', \'/random-image/\', array(
\'methods\' => \'GET, POST\',
\'callback\' => \'prefix__show_random_image\',
\'show_in_index\' => false,
) );
} );
/**
* Show random image
*/
function prefix__show_random_image(){
$image_ids = get_posts(
array(
\'post_type\' => \'attachment\',
\'post_mime_type\' => \'image\',
\'post_status\' => \'inherit\',
\'numberposts\' => 1,
\'orderby\' => \'rand\',
\'fields\' => \'ids\',
) );
// convert ids to urls
// $images = array_map( "wp_get_attachment_url", $image_ids );
// convert ids to paths
$images = array_map( "get_attached_file", $image_ids );
$image_id = $image_ids[ 0 ];
$image_path = $images[ 0 ];
// make sure url is readable -- if not, stop!
if ( ! is_readable( $image_path ) ) {
wp_die( "File is not readable: $image_path" );
}
$image = file_get_contents( $image_path );
$type = get_post_mime_type( $image_id );
if ( empty ( $type ) ) {
$type = "image/jpg";
}
// output headers and image data
nocache_headers();
header( "Content-type: $type;" );
header( "Content-Length: " . strlen( $image ) );
echo $image;
die();
}
