post json

//php

function ajax_posts_from_cats() {
    // $ids = isset( $_POST['ids'] );
    //update_post_meta( $post_id, 'select_post_cats', $ids );
    if ( !empty( $_POST['ids'] ) ) {
        $posts_loop = get_posts( [
            'post_type'   => 'question',
            'post_status' => 'publish',
            'category'    => intval($_POST['ids'],),
        ] );
    }

    echo wp_json_encode( $posts_loop );
    exit();
}

//JS

var post_ids = [];
			$(".random_question_selected_categories:checkbox:checked").each(function (i) {
				post_ids[i] = $(this).val();
			});

			var data = {
				action: "select_posts",
				ids: post_ids,
			};

			jQuery.post(ajax_url, data, function (response) {
				console.log(response);
			});