Question

get_user_meta( int $user_id,  string $key = '',  bool $single = false )

Retrieve user meta field for a user.

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description

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参数

$user_id

(int) (Required) User ID.

$key

(string) (Optional) The meta key to retrieve. By default, returns data for all keys.

Default value: ''

$single

(bool) (Optional) Whether to return a single value.

Default value: false

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返回值

(mixed) Will be an array if $single is false. Will be value of meta data field if $single is true.

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源代码

File: wp-includes/user.php

function get_user_meta($user_id, $key = '', $single = false) {
	return get_metadata('user', $user_id, $key, $single);
}

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更新日志

Version	description
3.0.0	Introduced.

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相关函数

Uses

• wp-includes/meta.php: get_metadata()

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Used By

• wp-admin/includes/class-wp-screen.php: WP_Screen::render_meta_boxes_preferences()
• wp-includes/class-wp-user-meta-session-tokens.php: WP_User_Meta_Session_Tokens::get_sessions()
• wp-admin/includes/ms.php: choose_primary_blog()
• wp-admin/includes/ms.php: new_user_email_admin_notice()
• wp-admin/includes/class-wp-internal-pointers.php: WP_Internal_Pointers::enqueue_scripts()
• wp-admin/includes/ajax-actions.php: wp_ajax_save_user_color_scheme()
• wp-admin/includes/ajax-actions.php: wp_ajax_dismiss_wp_pointer()
• wp-includes/class-wp-user.php: WP_User::__get()
• wp-includes/class-wp-user.php: WP_User::_init_caps()
• wp-includes/user.php: wp_update_user()
• wp-includes/user.php: get_blogs_of_user()
• wp-includes/user.php: is_user_member_of_blog()
• wp-includes/ms-functions.php: wpmu_create_blog()
• wp-includes/ms-functions.php: get_active_blog_for_user()
• wp-includes/ms-functions.php: add_user_to_blog()
• wp-includes/ms-functions.php: remove_user_from_blog()
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User Contributed Notes

1. Skip to note content You must log in to vote on the helpfulness of this noteVote results for this note: 3You must log in to vote on the helpfulness of this note Contributed by Codex

   Getting all meta data
   This example demonstrates leaving the $key argument blank, in order to retrieve all meta data for the given user (in this example, user_id = 9):

   
   <?php
     $all_meta_for_user = get_user_meta( 9 );
     print_r( $all_meta_for_user );
   ?>
   

   Results:

   Array ( [first_name] => Array ( [0] => Tom ) [last_name] => Array ( [0] => Auger)
[nickname] => Array ( [0] => tomauger ) [description] => etc.... )

   Note: In order to access the data in this example you need to dereference the array that is returned for each key, like so:

   
   $last_name = $all_meta_for_user['last_name'][0];
   

   To avoid this, you may want to run a simple array_map() on the results of get_user_meta() in order to take only the first index of each result (thus emulating what the $single argument does when $key is provided:

   
     $all_meta_for_user = array_map( function( $a ){ return $a[0]; }, get_user_meta( $user_id ) );
     print_r( $all_meta_for_user );
   

   Results:

   Array ( [first_name] => Tom [last_name] => Auger [nickname] => tomauger [description] => etc.... )

   Additionally, if you want to return ALL meta for a specific user and filter out empty values, you can run array_filter() on the results of the array_map() above:

   
   // Get all user meta data for $user_id
   $meta = get_user_meta( $user_id );
   
   // Filter out empty meta data
   $meta = array_filter( array_map( function( $a ) {
   	return $a[0];
   }, $meta ) );
   

If the key does not exist the function will return an empty string or an empty array depending on the value of the $single parameter

This example returns and then displays the last name for user id 9.

<?php 
  $user_id = 9;
  $key = 'last_name';
  $single = true;
  $user_last = get_user_meta( $user_id, $key, $single ); 
  echo '<p>The '. $key . ' value for user id ' . $user_id . ' is: ' . $user_last . '</p>'; 
?>

Result:

The last_name value for user id 9 is Franklin

To check if returned value is empty, ie does not exist, you could use something like:

global $current_user; 

get_currentuserinfo();

if ( $current_user ) {
	$permission = get_user_meta( $current_user->ID, 'some_meta' , true );
	
	if ( ! empty( $permission ) {
		// do stuff
	}
}
// works for both array and single values