这就是我最终得到的，效果很好。

功能。php部件

<?php

function scripts_enqueue() {
if(is_page(\'archives\')) {
    wp_enqueue_script(\'ajax_dropdown\', get_stylesheet_directory_uri() . \'/js/loadposts.js\',array(\'jquery\'));
    wp_localize_script( \'ajax_dropdown\', \'myajax\', array(\'custom_nonce\' => wp_create_nonce(\'nonce-ajax-dropdown\'), \'ajaxurl\' => admin_url( \'admin-ajax.php\' ) ) );
}
}

add_action( \'wp_enqueue_scripts\', \'scripts_enqueue\' );

function wp_ajax_load_posts(){

if(!wp_verify_nonce( $_GET[\'_wpnonce\'], \'nonce-ajax-dropdown\'))
    die( \'Go away!\' );

$args = array(
    \'year\' => trim($_GET[\'year\']),
    \'monthnum\' => trim($_GET[\'month\']),
    \'posts_per_page\' => -1,
    \'orderby\' => \'date\',
    \'cat\' => trim($_GET[\'cat\'] != "-1") ? trim($_GET[\'cat\']) : 0,
);

$ajaxsort = new WP_Query($args);
?>
<table id="archives-table">
    <?php if ($ajaxsort->have_posts()) : while ($ajaxsort->have_posts()) : $ajaxsort->the_post();?>
            <tr>
                <td><a href=\'<?php the_permalink(); ?>\'><?php the_title(); ?></a></td>
                <td><?php the_time(\'m/j/Y\'); ?></td>
        <td><?php comments_popup_link(\'0 Comments\', \'1 Comment\', \'% Comments\'); ?></td>
        <td><?php the_category();?>
            </tr>
    <?php 
        endwhile; else:
            echo "<tr><td style=\'text-align: center; font-size: 15px; padding: 5px;\'>Nothing found.</td></tr>";
        endif; 
    ?>
</table>
<?php
    exit;
}

add_action(\'wp_ajax_load_posts\', \'wp_ajax_load_posts\');
add_action(\'wp_ajax_nopriv_load_posts\', \'wp_ajax_load_posts\');

jQuery(document).ready(function($) {
$("#archive-browser select").change(function() {
    $(".message").hide();
    $("#archive-content").empty().html("<div style=\'text-align: center; padding: 30px;\'><img src=\'http://i.imgur.com/TA3o5.gif\' /></div>");
    var date = $(\'#month-choice option:selected\').val();
    var dateArray = $("#month-choice").val().split("/");
    var year = dateArray[3];
    var month = dateArray[4];
    var cat = $(\'#cat\').val();
    $.ajax({
        url: myajax.ajaxurl,
        type: \'GET\',
        data: {
            action: \'load_posts\',
            _wpnonce: myajax.custom_nonce,
            cat: cat,
            month: month,
            year: year,
        },
        success: function(data) {
            if (date == \'no-choice\' && cat == "-1") {
                $("#archive-content").empty().html(\'<table class="message" id="archives-table"><tr><td style="text-align: center; font-size: 15px; padding: 5px;">Please choose from above.</td></tr></table>\');
            } else {
                $("#archive-content").empty().html(data);
            }
        }
    });
    return false;
});
});