首先，让我在代码注释中描述完整的代码。请仔细阅读评论-

// By this below code you are returning TRUE to the filter \'tve_dash_enqueue_frontend\' filter. Which is I think, is turning something on.
add_filter( \'tve_dash_enqueue_frontend\', \'__return_true\' );

// Here you are hooking the `widget_posts_args` filter with `my_widget_posts_args` function.
add_filter( \'widget_posts_args\', \'my_widget_posts_args\');
function my_widget_posts_args($args) {
    // Look here, this is the twist.
    // with checking on `is_category()` function you are making this behavior for categories only.
    if ( is_category() ) {
        $cat = get_queried_object();
        return array(
            \'posts_per_page\' => 10,
            \'no_found_rows\' => true,
            \'post_status\' => \'publish\',
            \'ignore_sticky_posts\' => true,
            \'cat\' => $cat -> term_id//the current category id
        );
    }
    else {
        // If it is not category it is returning `$args` for normal behaviour.
        return $args;

    }
}

因此，要使其在单个页面上工作，您需要修改if 条件块和代码块如下所示-

// By this below code you are returning TRUE to the filter \'tve_dash_enqueue_frontend\' filter. Which is I think, is turning something on.
add_filter( \'tve_dash_enqueue_frontend\', \'__return_true\' );

// Here you are hooking the `widget_posts_args` filter with `my_widget_posts_args` function.
add_filter( \'widget_posts_args\', \'my_widget_posts_args\' );
function my_widget_posts_args( $args ) {
    // Look here, this is the twist.
    // with checking on `is_category()` function you are aking this behaviour for categories only.
    if ( is_category() ) {
        $cat = get_queried_object();
        return array(
            \'posts_per_page\' => 10,
            \'no_found_rows\' => true,
            \'post_status\' => \'publish\',
            \'ignore_sticky_posts\' => true,
            \'cat\' => $cat -> term_id, //the current category id
        );
    } else {
        // If it is a single post then it\'ll return posts from the category(s) of current post.
        global $post;
        return array(
            \'posts_per_page\' => 10,
            \'no_found_rows\' => true,
            \'post_status\' => \'publish\',
            \'ignore_sticky_posts\' => true,
            \'category__in\' => get_the_category( $post->ID ),
        );

    }
}

注意：如果它是一篇文章，那么它将在widget上显示当前文章类别中的文章。