我创建了一个自定义RESTAPI来获取帖子

add_action( \'rest_api_init\', \'custom_api_get_all_posts\' ); 



function custom_api_get_all_posts() {
    register_rest_route( \'custom/v1\', \'/all-posts\', array(
        \'methods\' => \'GET\',
        \'callback\' => \'custom_api_get_all_posts_callback\'
    ));
}

function custom_api_get_all_posts_callback( $request ) {
    // Initialize the array that will receive the posts\' data. 
    $posts_data = array();
    // Receive and set the page parameter from the $request for pagination purposes
    $paged = $request->get_param( \'page\' );
    $paged = ( isset( $paged ) || ! ( empty( $paged ) ) ) ? $paged : 1; 
    // Get the posts using the \'post\' and \'news\' post types
    $posts = get_posts( array(
            \'paged\' => $paged,
            \'post__not_in\' => get_option( \'sticky_posts\' ),
            \'posts_per_page\' => 10,            
            \'post_type\' => listing,
            \'tax_query\' => array(
                array (
                \'taxonomy\' => \'flux_rss\',
                \'field\' => \'slug\',
                \'terms\' => \'oui\',
                )
            ), 
        )
    ); 


// Loop through the posts and push the desired data to the array we\'ve initialized earlier in the form of an object
foreach( $posts as $post ) {

    $id = $post->ID; 
    $post_thumbnail = ( has_post_thumbnail( $id ) ) ? get_the_post_thumbnail_url( $id ) : null;

    $posts_data[] = (object) array( 
        \'id\' => $id, 
        \'title\' => $post->post_title,
        \'excerpt\' => wp_json_encode($post->post_excerpt), 
        \'link\' => $post->guid,
        \'featured_img_src\' => $post_thumbnail
    );
}                  
return $posts_data;                   

但是我在响应中得到了一些特殊的字符，因此如何将json响应转换为utf8

[{
    "id": 2087,
    "title": "Avec l\\u2019ONPA",
    "excerpt": "\\"Avec cette association cr\\\\u00e9\\\\u00e9e en 1971, les s\\\\u00e9niors de 55 ans et plus, en activit\\\\u00e9 professionnelle ou non, et vivant \\\\u00e0 domicile, m\\\\u00e8nent une vie active...\\"",
    "link": "http:\\/\\/localhost\\/focus\\/?post_type=listing&p=2087",
    "featured_img_src": "http:\\/\\/localhost\\/focus\\/wp-content\\/uploads\\/2018\\/05\\/avec-lonpa.jpg"
},