模版标签/get posts

来自WordPress中文文档
跳转至: 导航搜索

wordpress.org.cn

Description

The most appropriate use for get_posts is to create an array of posts based on a set of parameters. It retrieves a list of latest posts or posts matching this criteria. get_posts can also be used to create Multiple Loops, though a more direct reference to WP_Query using new WP_Query is preferred in this case.

The parameters of get_posts are similar to those of get_pages but is implemented quite differently, and should be used in appropriate scenarios. get_posts uses WP_Query, whereas get_pages queries the database more directly. Each have parameters that reflect this difference in implementation.

query_posts also uses WP_Query, but is not recommended because it directly alters the main loop by changing the variables of the global variable $wp_query. get_posts, on the other hand, simply references a new WP_Query object, and therefore does not effect or alter the main loop.

If you would like to alter the main query before it is executed, you can hook into it using pre_get_posts. If you would just like to call an array of posts based on a small and simple set of parameters within a page, then get_posts is your best option.

Usage

%%% <?php $posts_array = get_posts( $args ); ?> %%%

Default Usage

<?php $args = array(
	'posts_per_page'  => 5,
	'numberposts'     => 5,
	'offset'          => 0,
	'category'        => '',
	'orderby'         => 'post_date',
	'order'           => 'DESC',
	'include'         => '',
	'exclude'         => '',
	'meta_key'        => '',
	'meta_value'      => '',
	'post_type'       => 'post',
	'post_mime_type'  => '',
	'post_parent'     => '',
	'post_status'     => 'publish',
	'suppress_filters' => true ); ?>

Note: 'numberposts' and 'posts_per_page' can be used interchangeably.

Parameters

For full parameters list see WP_Query

See also get_pages() for example parameter usage.

get_posts() makes use of the WP_Query class to fetch posts. See the parameters section of the WP_Query documentation for a list of parameters that this function accepts.

Note: get_posts uses 'suppress_filters' => true as default, while query_posts() applies filters by default, this can be confusing when using query-modifying plugins, like WPML. Also note that even if 'suppress_filters' is true, any filters attached to pre_get_posts are still applied—only filters attached on 'posts_*' or 'comment_feed_*' are suppressed.

Note: The category parameter needs to be the ID of the category, and not the category name.

Note: The category parameter can be a comma separated list of categories, as the get_posts() function passes the 'category' parameter directly into WP_Query as 'cat'.

tt$post_mime_type/tt
(string|array) (Optional) List of mime types or comma separated string of mime types.
Default: Nonenoinclude

div class=template-description style=padding: 0 1.5em; border: 1px solid #eeeeee; background-color: #f9f9f9

Notes

This template is for standardizing how parameters look in the Function Reference and in Template Tags. Here is an example of this template being called: prenowiki检查到模板循环:模板:Parameter/nowiki/pre 检查到模板循环:模板:Parameter

The usage of this template is below: prenowiki检查到模板循环:模板:Parameter/nowiki/pre Let's take a closer look at the parameters..

name
The name of the parameter.
datatype
The datatype that should be given for this parameter when called.
  • string
  • integer
  • boolean
  • mixed
description
A short description of the parameter.
importance
Set this parameter to optional if the parameter is optional. Otherwise, do not declare this parameter—it defaults to required.
  • required
  • optional
default
If this parameter is optional, ttdefault/tt is the value that will be used if the parameter is not declared.

wordpress.org.cn /div /noinclude

Return Value

(array) 
List of post objects. See get_post() return values.

Unlike get_pages(), get_posts() will return private pages in the appropriate context (i.e., for an administrator). (See: Andreas Kirsch, WordPress Hacking II, January 24, 2009-- accessed 2012-11-09.)

Examples

Posts list with offset

If you have your blog configured to show just one post on the front page, but also want to list links to the previous five posts in category ID 1, you can use this:

<ul>
<?php
global $post;
$args = array( 'numberposts' => 5, 'offset'=> 1, 'category' => 1 );
$myposts = get_posts( $args );
foreach( $myposts as $post ) :	setup_postdata($post); ?>
	<li><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></li>
<?php endforeach; ?>
</ul>

Note: With use of the offset, the above query should be used only on a category that has more than one post in it, otherwise there'll be no output.

Reset after Postlists with offset

If you need after the loop, the post you had before joining the foreach, you can use this:

<ul>
<?php
global $post;
$tmp_post = $post;
$args = array( 'numberposts' => 5, 'offset'=> 1, 'category' => 1 );
$myposts = get_posts( $args );
foreach( $myposts as $post ) : setup_postdata($post); ?>
	<li><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></li>
<?php endforeach; ?>
<?php $post = $tmp_post; ?>
</ul>

Access all post data

Some post-related data is not available to get_posts by default, such as post content through the_content(), or the numeric ID. This is resolved by calling an internal function setup_postdata(), with the $post array as its argument:

<?php
$args = array( 'numberposts' => 3 );
$lastposts = get_posts( $args );
foreach($lastposts as $post) : setup_postdata($post); ?>
	<h2><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></h2>
	<?php the_content(); ?>
<?php endforeach; ?>

To access a post's ID or content without calling setup_postdata(), or in fact any post-specific data (data retained in the posts table), you can use $post->COLUMN, where COLUMN is the table column name for the data. So $post->ID holds the ID, $post->post_content the content, and so on. To display or print this data on your page use the PHP echo command, like so:

<?php echo $post->ID; ?>

Latest posts ordered by title

To show the last ten posts sorted alphabetically in ascending order, the following will display their post date, title and excerpt:

<?php
$args = array( 'numberposts' => 10, 'order'=> 'ASC', 'orderby' => 'title' );
$postslist = get_posts( $args );
foreach ($postslist as $post) :  setup_postdata($post); ?> 
	<div>
		<?php the_date(); ?>
		<br />
		<?php the_title(); ?>   
		<?php the_excerpt(); ?>
	</div>
<?php endforeach; ?>

Random posts

Display a list of 5 posts selected randomly by using the MySQL RAND() function for the orderby parameter value:

<ul>
<?php
$args = array( 'numberposts' => 5, 'orderby' => 'rand' );
$rand_posts = get_posts( $args );
foreach( $rand_posts as $post ) : ?>
	<li><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></li>
<?php endforeach; ?>
</ul>

Show all attachments

Do this outside any Loops in your template.

<?php
$args = array( 'post_type' => 'attachment', 'numberposts' => -1, 'post_status' => 'any', 'post_parent' => null ); 
$attachments = get_posts( $args );
if ($attachments) {
	foreach ( $attachments as $post ) {
		setup_postdata($post);
		the_title();
		the_attachment_link($post->ID, false);
		the_excerpt();
	}
}
?>

Show attachments for the current post

Do this inside The Loop (where $post->ID is available).

<?php
$args = array( 'post_type' => 'attachment', 'numberposts' => -1, 'post_status' =>'any', 'post_parent' => $post->ID ); 
$attachments = get_posts($args);
if ($attachments) {
	foreach ( $attachments as $attachment ) {
		echo apply_filters( 'the_title' , $attachment->post_title );
		the_attachment_link( $attachment->ID , false );
	}
}
?>

Get a post by its slug

Allows you to get a post ID by post slug. The caller_get_posts argument excludes sticky posts from this custom query.

<?php
$the_slug = 'my_slug';
$args=array(
  'name' => $the_slug,
  'post_type' => 'post',
  'post_status' => 'publish',
  'numberposts' => 1
);
$my_posts = get_posts($args);
if( $my_posts ) {
echo 'ID on the first post found '.$my_posts[0]->ID;
}
?>

Taxonomy Parameters

Show posts associated with certain taxonomy. If specifying a taxonomy registered to a custom post type then instead of using 'category' you would use '{custom_taxonomy_name}'. For instance, if you had a custom taxonomy called "genre" and wanted to only show posts from the "jazz" genre you would use the below code.

<?php
$args = array(
   'numberposts' => 8,
   'orderby' => 'rand',
   'post_type' => 'albums',
   'genre' => 'jazz',
   'post_status' => 'publish'
);
$show_albums = get_posts ( $args );
?>

Following example displays posts tagged with 'jazz', under 'genre' custom taxonomy, using 'tax_query':

$args = array(
	'tax_query' => array(
		array(
			'taxonomy' => 'genre',
			'field' => 'slug',
			'terms' => 'jazz'
		)
	)
);
$postslist = get_posts( $args );

Refer to the taxonomy parameters section of the WP_Query documentation for more examples.

Custom Field Parameters

Show posts associated with a certain custom field. Following example displays posts from the 'product' post type that have meta key 'featured' with value 'yes', using 'meta_query':

$args = array(
	'post_type' => 'product',
	'meta_query' => array(
		array(
			'key' => 'featured',
			'value' => 'yes',
		)
	)
 );
$postslist = get_posts( $args );

Refer to the custom fields parameters section of the WP_Query documentation for more examples.

Change Log

Source File

get_posts() is located in onlyincludecodewp-includes/post.php/code/onlyinclude

div class=template-description style=padding: 0 1.5em; border: 1px solid #eeeeee; background-color: #f9f9f9

Template Description

Link to the source code on http://core.trac.wordpress.org/browser/.

Parameters

  1. filename
  2. (option) path to codetag/code (version) or codetrunk/code. This option is only used for a new function.br /Default: codetrunk/code -- trunk is the latest bleeding edge development version of WordPress.

Usage

Link to the stable version: pre检查到模板循环:模板:Trac/pre

Link to trunk: pre检查到模板循环:模板:Trac/pre

/div

wordpress.org.cn.

Related

includeonlydiv style=clear:both; background-color:#F7F7F7; border:1px solid #CCCCCC; color:#000000; padding:7px; margin:0.5em auto 0.5em auto; vertical-align:middle;See also index of Function Reference and index of Template Tags./div/includeonlynoinclude

Description

This Template is used by Codex:Template Messages.

Usage

pre 检查到模板循环:模板:Message /pre

Result

检查到模板循环:模板:Message

/noinclude