如何在几年和几个月内对 Wordpress 帖子进行分组？

Question

我正在尝试使用后查询和输出中的以下结构创建一个函数：

2021 一月 1.帖子标题 2.帖子标题 行进 3.帖子标题 2020 可能 4.帖子标题

这是我到目前为止所做的：

global $post;

$posts = get_posts( array(
    'post_type' => 'history',
    'orderby'   => 'date'
) );

$_year_mon = '';
$_has_grp = false;

foreach ( $posts as $post ) {
    setup_postdata( $post );

    $time = strtotime( $post->post_date );
    $year = date( 'Y', $time );
    $mon = date( 'F', $time );
    $year_mon = "$year-$mon";

    if ( $year_mon !== $_year_mon ) {
        // Close previous group, if any.
        if ( $_has_grp ) {
            echo '</div>';
            echo '</div>';
        }
        $_has_grp = true;

        echo '<div class="year">';
        echo "<span>$year</span>";

        echo '<div class="month">';
        echo "<span>$mon</span>";
    }

    // Display post title.
    if ( $title = get_the_title() ) {
        echo "<div>$title</div>";
    } else {
        echo "<div>#{$post->ID}</div>";
    }

    $_year_mon = $year_mon;
}

if ( $_has_grp ) {
    echo '</div>';
    echo '</div>';
}

wp_reset_postdata();

问题是具有多个月份的同一年没有分组在一个元素中..

当前输出：

2021 一月 1.帖子标题 2.帖子标题 2021 行进 3.帖子标题 2020 可能 4.帖子标题

Answer 1

以下解决方案已经过全面测试，并且对于默认的 wordpress post 类型可以无缝运行。如果您想为具有自己的自定义字段的自定义帖子类型运行它，那么您可能会遇到一些差异。因此，请随时根据需要为您自己的自定义帖子类型进行自定义。

正如我们在this question 上讨论的那样，当您使用get_posts 时，它将返回post objects。每个post object 包含以下属性/数据：

WP_Post Object
(
    [ID] =>
    [post_author] =>
    [post_date] => 
    [post_date_gmt] => 
    [post_content] => 
    [post_title] => 
    [post_excerpt] => 
    [post_status] =>
    [comment_status] =>
    [ping_status] => 
    [post_password] => 
    [post_name] =>
    [to_ping] => 
    [pinged] => 
    [post_modified] => 
    [post_modified_gmt] =>
    [post_content_filtered] => 
    [post_parent] => 
    [guid] => 
    [menu_order] =>
    [post_type] =>
    [post_mime_type] => 
    [comment_count] =>
    [filter] =>
)

例如，如果您需要帖子的title、content、author、exerpt，那么您可以创建一个多维数组并使用array_push 函数来创建您的自定义数组，如下所示：

$posts = get_posts(array(
  'post_type' => 'history', // Since 'history' is a custom post type, I tested it on 'post'
//'post_type' => 'post'
  'posts_per_page' => -1,
  'orderby'   => 'date'
));

// You could see the number of posts for your query
echo "Number of posts found: ". count($posts) . "<br>";

$your_custom_array_yearly = array();

foreach ($posts as $post) {
  setup_postdata($post);
  $time = strtotime($post->post_date);
  $year = date('Y', $time);
  $mon = date('F', $time);

  if (!($your_custom_array_yearly[$year][$mon])) {
    $your_custom_array_yearly[$year][$mon] = array();
    array_push(
      $your_custom_array_yearly[$year][$mon],
      [
        'title'   => $post->post_title,
        'excerpt' => $post->post_excerpt,
        'author'  => $post->post_author,
        'content' => $post->post_content,
      ]
    );
  } else {
    array_push(
      $your_custom_array_yearly[$year][$mon],
      [
        'title'   => $post->post_title,
        'excerpt' => $post->post_excerpt,
        'author'  => $post->post_author,
        'content' => $post->post_content,
      ]
    );
  };
}

wp_reset_postdata();

为了调试/调查数组，你可以使用这个：

echo "<pre>";
print_r($your_custom_array_yearly);
echo "</pre>";

既然您有自己的自定义数组，那么您可以循环遍历它并输出您的数据：

foreach ((array)$your_custom_array_yearly as $yearly => $yvalue) {
  echo $yearly . ": <br>";
  echo "<ul>";
  foreach ($yvalue as $monthly => $mvalue) {
    echo "<li>" . $monthly . ": </li><ul>";
    foreach ($mvalue as $monthly_k => $monthly_v) {
      foreach ($monthly_v as $post_title_k => $post_title_v) {
        echo "<li>" . $post_title_k . ": " . $post_title_v . "</li></ul>";
      }
    }
  }
  echo "</ul>";
}

以上代码会输出如下结果：

2021:
  January:
    1.Title: Post Title
    1.Excerpt: Post excerpt
    1.Author: Post author
    1.Content: Post content
    2.Title: Post Title
    2.Excerpt: Post excerpt
    2.Author: Post author
    2.Content: Post content
  March:
    3.Title: Post Title
    3.Excerpt: Post excerpt
    3.Author: Post author
    3.Content: Post content

2020:
  May:
    4.Title: Post Title
    4.Excerpt: Post excerpt
    4.Author: Post author
    4.Content: Post content

Answer 2

像这样创建一个多维数组并打印出来。您可能会得到适当的结果。

$master = [];

foreach ( $posts as $post ) {
    setup_postdata( $post );

    $time = strtotime( $post->post_date );
    $year = date( 'Y', $time );
    $mon = date( 'F', $time );
    
    $master[$year][$mon][] = $post;
}

wp_reset_postdata();

echo '<pre>';
print_r($master);
echo '</pre>';