WordPress系统默认使用Gravatar头像，用户（包括访客评论）的头像调取都是根据所留邮箱匹配的Gravatar头像。本文要做的是存代码实现头像使用用户本地自定义上传的图片。

我们可以直接将代码集成到主题，将代码直接放入functions.php文件即可。
由于代码较长，笔者强烈建议将其写成单独文件，并在在functions.php引入。
方法：下载author-avatars.php文件 点我下载    提取码：kwi6
放入主题文件夹（如笔者将此类功能都放入主题中的inc文件夹）然后在functions.php引入

//用户自定义头像功能
include (TEMPLATEPATH . '/inc/author-avatars.php');

至此，你的WordPress站点已经支持用户自定义头像了，如果用户同时设置了Gravatar和本地上传头像，那么优先显示本地上传的头像，头像调取函数不变：get_simple_local_avatar 或 get_avatar
附author-avatars.php代码

<?php
/**
 Plugin Name: Simple Local Avatars
 Plugin URI: http://get10up.com/plugins/simple-local-avatars-wordpress/
 Description: Adds an avatar upload field to user profiles if the current user has media permissions. Generates requested sizes on demand just like Gravatar! Simple and lightweight.
 Version: 1.3.1
 Author: Jake Goldman (10up LLC), Oomph Inc
 Author URI: http://get10up.com
Plugin: Copyright 2011 Jake Goldman (email : jake@get10up.com)
This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; either version 2 of the License, or
 (at your option) any later version.
This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 GNU General Public License for more details.
You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
NOTE: Previous versions may have accidentally and incorrectly attributed the
 copyright to employers of Mr. Goldman. While credit is given to all contributors
 to the current version, including Mr. Goldman's employers, the copyright belongs
 - and has always belonged - to Mr. Goldman, personally.
*/
/**
 * add field to user profiles
 */
class Simple_Local_Avatars {
 private $user_id_being_edited;
public function __construct() {
 add_filter( 'get_avatar', array( $this, 'get_avatar' ), 10, 5 );
add_action( 'admin_init', array( $this, 'admin_init' ) );
add_action( 'show_user_profile', array( $this, 'edit_user_profile' ) );
 add_action( 'edit_user_profile', array( $this, 'edit_user_profile' ) );
add_action( 'personal_options_update', array( $this, 'edit_user_profile_update' ) );
 add_action( 'edit_user_profile_update', array( $this, 'edit_user_profile_update' ) );
add_filter( 'avatar_defaults', array( $this, 'avatar_defaults' ) );
 }
public function get_avatar( $avatar = '', $id_or_email, $size = 96, $default = '', $alt = false ) {
if ( is_numeric($id_or_email) )
 $user_id = (int) $id_or_email;
 elseif ( is_string( $id_or_email ) && ( $user = get_user_by( 'email', $id_or_email ) ) )
 $user_id = $user->ID;
 elseif ( is_object( $id_or_email ) && ! empty( $id_or_email->user_id ) )
 $user_id = (int) $id_or_email->user_id;
if ( empty( $user_id ) )
 return $avatar;
$local_avatars = get_user_meta( $user_id, 'simple_local_avatar', true );
if ( empty( $local_avatars ) || empty( $local_avatars['full'] ) )
 return $avatar;
$size = (int) $size;
if ( empty( $alt ) )
 $alt = get_the_author_meta( 'display_name', $user_id );
// generate a new size
 if ( empty( $local_avatars[$size] ) ) {
 $upload_path = wp_upload_dir();
 $avatar_full_path = str_replace( $upload_path['baseurl'], $upload_path['basedir'], $local_avatars['full'] );
 $image_sized = image_resize( $avatar_full_path, $size, $size, true );
 // deal with original being >= to original image (or lack of sizing ability)
 $local_avatars[$size] = is_wp_error($image_sized) ? $local_avatars[$size] = $local_avatars['full'] : str_replace( $upload_path['basedir'], $upload_path['baseurl'], $image_sized );
 // save updated avatar sizes
 update_user_meta( $user_id, 'simple_local_avatar', $local_avatars );
 } elseif ( substr( $local_avatars[$size], 0, 4 ) != 'http' ) {
 $local_avatars[$size] = home_url( $local_avatars[$size] );
 }
$author_class = is_author( $user_id ) ? ' current-author' : '' ;
 $avatar = "<img alt='" . esc_attr( $alt ) . "' src='" . $local_avatars[$size] . "' class='avatar avatar-{$size}{$author_class} photo' height='{$size}' width='{$size}' />";
return apply_filters( 'simple_local_avatar', $avatar );
 }
public function admin_init() {
 //load_plugin_textdomain( 'simple-local-avatars', false, dirname( plugin_basename( __FILE__ ) ) . '/localization/' );
register_setting( 'discussion', 'simple_local_avatars_caps', array( $this, 'sanitize_options' ) );
 add_settings_field( 'simple-local-avatars-caps', __('上传头像权限','simple-local-avatars'), array( $this, 'avatar_settings_field' ), 'discussion', 'avatars' );
 }
public function sanitize_options( $input ) {
 $new_input['simple_local_avatars_caps'] = empty( $input['simple_local_avatars_caps'] ) ? 0 : 1;
 return $new_input;
 }
public function avatar_settings_field( $args ) {
 $options = get_option('simple_local_avatars_caps');
echo '
 <label for="simple_local_avatars_caps">
 <input type="checkbox" name="simple_local_avatars_caps" id="simple_local_avatars_caps" value="1" ' . @checked( $options['simple_local_avatars_caps'], 1, false ) . ' />
 ' . __('仅具有头像上传权限的用户具有设置本地头像权限（作者及更高等级角色）。','simple-local-avatars') . '
 </label>
 ';
 }
public function edit_user_profile( $profileuser ) {
 ?>
 <h3><?php _e( '头像','simple-local-avatars' ); ?></h3>
<table class="form-table">
 <tr>
 <th><label for="simple-local-avatar"><?php _e('上传头像','simple-local-avatars'); ?></label></th>
 <td style="width: 50px;" valign="top">
 <?php echo get_avatar( $profileuser->ID ); ?>
 </td>
 <td>
 <?php
 $options = get_option('simple_local_avatars_caps');
if ( empty($options['simple_local_avatars_caps']) || current_user_can('upload_files') ) {
 do_action( 'simple_local_avatar_notices' );
 wp_nonce_field( 'simple_local_avatar_nonce', '_simple_local_avatar_nonce', false );
 ?>
 <input type="file" name="simple-local-avatar" id="simple-local-avatar" /><br />
 <?php
 if ( empty( $profileuser->simple_local_avatar ) )
 echo '<span class="description">' . __('尚未设置本地头像，请点击“浏览”按钮上传本地头像。','simple-local-avatars') . '</span>';
 else
 echo '
 <input type="checkbox" name="simple-local-avatar-erase" value="1" /> ' . __('移除本地头像','simple-local-avatars') . '<br />
 <span class="description">' . __('如需要修改本地头像，请重新上传新头像。如需要移除本地头像，请选中上方的“移除本地头像”复选框并更新个人资料即可。<br/>移除本地头像后，将恢复使用 Gravatar 头像。','simple-local-avatars') . '</span>
 ';
 } else {
 if ( empty( $profileuser->simple_local_avatar ) )
 echo '<span class="description">' . __('尚未设置本地头像，请在 Gravatar.com 网站设置头像。','simple-local-avatars') . '</span>';
 else
 echo '<span class="description">' . __('你没有头像上传权限，如需要修改本地头像，请联系站点管理员。','simple-local-avatars') . '</span>';
 }
 ?>
 </td>
 </tr>
 </table>
 <script type="text/javascript">var form = document.getElementById('your-profile');form.encoding = 'multipart/form-data';form.setAttribute('enctype', 'multipart/form-data');</script>
 <?php
 }
public function edit_user_profile_update( $user_id ) {
 if ( ! isset( $_POST['_simple_local_avatar_nonce'] ) || ! wp_verify_nonce( $_POST['_simple_local_avatar_nonce'], 'simple_local_avatar_nonce' ) ) //security
 return;
if ( ! empty( $_FILES['simple-local-avatar']['name'] ) ) {
 $mimes = array(
 'jpg|jpeg|jpe' => 'image/jpeg',
 'gif' => 'image/gif',
 'png' => 'image/png',
 'bmp' => 'image/bmp',
 'tif|tiff' => 'image/tiff'
 );
// front end (theme my profile etc) support
 if ( ! function_exists( 'wp_handle_upload' ) )
 require_once( ABSPATH . 'wp-admin/includes/file.php' );
$this->avatar_delete( $user_id ); // delete old images if successful
// need to be more secure since low privelege users can upload
 if ( strstr( $_FILES['simple-local-avatar']['name'], '.php' ) )
 wp_die('For security reasons, the extension ".php" cannot be in your file name.');
$this->user_id_being_edited = $user_id; // make user_id known to unique_filename_callback function
 $avatar = wp_handle_upload( $_FILES['simple-local-avatar'], array( 'mimes' => $mimes, 'test_form' => false, 'unique_filename_callback' => array( $this, 'unique_filename_callback' ) ) );
if ( empty($avatar['file']) ) { // handle failures
 switch ( $avatar['error'] ) {
 case 'File type does not meet security guidelines. Try another.' :
 add_action( 'user_profile_update_errors', create_function('$a','$a->add("avatar_error",__("请上传有效的图片文件。","simple-local-avatars"));') );
 break;
 default :
 add_action( 'user_profile_update_errors', create_function('$a','$a->add("avatar_error","<strong>".__("上传头像过程中出现以下错误：","simple-local-avatars")."</strong> ' . esc_attr( $avatar['error'] ) . '");') );
 }
return;
 }
update_user_meta( $user_id, 'simple_local_avatar', array( 'full' => $avatar['url'] ) ); // save user information (overwriting old)
 } elseif ( ! empty( $_POST['simple-local-avatar-erase'] ) ) {
 $this->avatar_delete( $user_id );
 }
 }
/**
 * remove the custom get_avatar hook for the default avatar list output on options-discussion.php
 */
 public function avatar_defaults( $avatar_defaults ) {
 remove_action( 'get_avatar', array( $this, 'get_avatar' ) );
 return $avatar_defaults;
 }
/**
 * delete avatars based on user_id
 */
 public function avatar_delete( $user_id ) {
 $old_avatars = get_user_meta( $user_id, 'simple_local_avatar', true );
 $upload_path = wp_upload_dir();
if ( is_array($old_avatars) ) {
 foreach ($old_avatars as $old_avatar ) {
 $old_avatar_path = str_replace( $upload_path['baseurl'], $upload_path['basedir'], $old_avatar );
 @unlink( $old_avatar_path );
 }
 }
delete_user_meta( $user_id, 'simple_local_avatar' );
 }
public function unique_filename_callback( $dir, $name, $ext ) {
 $user = get_user_by( 'id', (int) $this->user_id_being_edited );
 $name = $base_name = sanitize_file_name( $user->user_login . '_avatar' );
 $number = 1;
while ( file_exists( $dir . "/$name$ext" ) ) {
 $name = $base_name . '_' . $number;
 $number++;
 }
return $name . $ext;
 }
}
$simple_local_avatars = new Simple_Local_Avatars;
/**
 * more efficient to call simple local avatar directly in theme and avoid gravatar setup
 *
 * @param int|string|object $id_or_email A user ID, email address, or comment object
 * @param int $size Size of the avatar image
 * @param string $default URL to a default image to use if no avatar is available
 * @param string $alt Alternate text to use in image tag. Defaults to blank
 * @return string <img> tag for the user's avatar
 */
function get_simple_local_avatar( $id_or_email, $size = '96', $default = '', $alt = false ) {
 global $simple_local_avatars;
 $avatar = $simple_local_avatars->get_avatar( '', $id_or_email, $size, $default, $alt );
if ( empty ( $avatar ) )
 $avatar = get_avatar( $id_or_email, $size, $default, $alt );
return $avatar;
}

原文：https://www.yaxi.net/2017-08-22/1551.html