最近很多用户问我，能否在WordPress主题中添加一个用户关注功能，答案是肯定的，那么WordPress如何实现用户关注功能？首先，将下面的代码放到您的functions.php文件中。
function wpdiary_user_guanzhu(){
if(!get_current_user_id()){
exit(json_encode([\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’msg\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’=>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’请登录!\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’]));
}
if( $_POST[\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’user\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’]==get_current_user_id()){
exit(json_encode([\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’msg\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’=>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’你不能关注自己!\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’]));
}
$user = $_POST[\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’user\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’];
$meta = get_user_meta(get_current_user_id(),\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,true);
$bguanzhu1 = explode(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,get_user_meta($user,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’bguanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,true));
$bguanzhu = array_filter($bguanzhu1);
$guanzhu1 = explode(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,get_user_meta(get_current_user_id(),\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,true));
$guanzhu = array_filter($guanzhu1);
if(in_array($user,$guanzhu)){
foreach($guanzhu as $k=>$v){
if($v==$user){
unset($guanzhu[$k]);
}
}
foreach($bguanzhu as $k=>$v){
if($v==get_current_user_id()){
unset($bguanzhu[$k]);
}
}
update_user_meta(get_current_user_id(),\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,implode(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”,$guanzhu));
update_user_meta($user,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’bguanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,implode(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”,$bguanzhu));
exit(json_encode([\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’msg\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’=>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’取消成功!\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’]));
}else{
array_push($guanzhu,$user);
array_push($bguanzhu,get_current_user_id());
update_user_meta(get_current_user_id(),\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,implode(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”,$guanzhu));
update_user_meta($user,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’bguanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,implode(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”,$bguanzhu));
exit(json_encode([\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’msg\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’=>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’关注成功!\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’]));
}
}
add_action(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’wp_ajax_guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’wpdiary_user_guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’);
add_action(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’wp_ajax_nopriv_guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’wpdiary_user_guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’);
//获取指定用户关注数量
function get_wpdiary_guanzhu_count($authorID){
$meta = get_user_meta($authorID,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,true);
if($meta){
$guanzhu = explode(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”,get_user_meta($authorID,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,true));
return count($guanzhu);
}else{
return 0;
}
}
//获取指定用户被关注数量
function get_wpdiary_bguanzhu_count($authorID){
$meta = get_user_meta($authorID,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’bguanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,true);
if($meta){
$bguanzhu = explode(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”,get_user_meta($authorID,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’bguanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,true));
return count($bguanzhu);
}else{
return 0;
}
}
其次，消息提示使用了layer这个jQuery弹出层插件，所以，您还需要在主题中引入这个框架的文件（下载地址：http://res.layui.com/static/download/layer/layer-v3.1.1.zip），下载后把整个文件夹放到您的主题目录中，然后在主题头部引入layer.js，并将下面的JS代码放到您的footer.php中。
<script>
$(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’a.addfollow\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’).click(function(){
var user = $(this).attr(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’user\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’);
$.ajax({
url: \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”/wp-admin/admin-ajax.php\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”,
type:\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’post\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,
dataType:\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’json\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,
data:{action:\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,user:user},
success: function(data){
layer.alert(data.msg, function(){
location.reload();
});
}
});
});
</script>
第三，将关注按钮放到您需要放的地方，比如用户列表中或作者存档页，关注按钮代码如下：
<?php
$meta = get_user_meta(get_current_user_id(),\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,true);
$user = ‘要被关注的用户的ID’
if($meta){
$guanzhu = explode(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,$meta);
}else{
$guanzhu = array();
}
if(in_array($user,$guanzhu)){?>
<a href=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”javascript:;\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” user=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”<?php echo $user;?>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”addfollow focus-link\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>+取消关注</a>
<?php }else{?>
<a href=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”javascript:;\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” user=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”<?php echo $user;?>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”addfollow focus-link\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>+ 关注</a>
<?php }?>
第四，获取指定用户关注和被关注数量：
<?php echo get_wpdiary_guanzhu_count(‘用户ID’);?>//获取指定用户关注数量
<?php echo get_wpdiary_bguanzhu_count(‘用户ID’);?>//获取指定用户被关注数量
第五，如何获取当前登录用户关注的用户的列表：
<?php
$user_id = get_current_user_id();//当前登录用户id，也可以指定为某个ID的用户，这样获取到的就是指定ID的用户的关注列表
$meta = get_user_meta($user_id,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,true);
$guanzhulist = explode(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,$meta );
$users = get_users(array(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’include\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’=>$guanzhulist));
?>
<?php foreach($users as $user){ ?>
<li class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”pic-btn-li\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>
<div class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”li-pic\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>
<a href=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”https://www.wpzt.net/<?php%20echo%20get_author_posts_url(%20$user->ID);%20?>/?userid=<?php%20echo%20$user->ID;?>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” target=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”_blank\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”li-link\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>
<?php echo get_avatar($user->ID);?>
</a>
</div>
<div class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”li-dec\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>
<p class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”dec-name\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>
<a href=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”https://www.wpzt.net/<?php%20echo%20get_author_posts_url(%20$user->ID);%20?>/?userid=<?php%20echo%20$user->ID;?>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” target=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”_blank\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”dec-name-link\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”><?php echo $user->nickname;?></a>
</p>
<p class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”dec-sub\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>
<span class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”dec-fans\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>粉丝 <?php echo get_wpdiary_bguanzhu_count($user->ID);?></span>
</p>
</div>
<a href=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”javascript:;\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” user=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”<?php echo $user->ID;?>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”addfollow sp-mod-button\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” title=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”关注他\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>取消</a>
</li>
<?php } ?>
第六，获取关注过当前登录用户的列表（被关注列表，也可以说是粉丝列表）：
<?php
$user_id = get_current_user_id();//当前登录用户id，也可以指定为某个ID的用户，这样获取到的就是关注过指定ID的用户列表（粉丝列表）
$bguanzhu = get_user_meta($user_id,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’bguanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,true);
$fanslist = explode(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,$bguanzhu );
$fans = get_users(array(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’include\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’=>$fanslist));
?>
<?php foreach($fans as $fensi){ ?>
<li class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”pic-btn-li\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>
<div class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”li-pic\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>
<a href=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”https://www.wpzt.net/<?php%20echo%20get_author_posts_url(%20$fensi->ID);%20?>/?userid=<?php%20echo%20$fensi->ID;?>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” target=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”_blank\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”li-link\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>
<?php echo get_avatar($fensi->ID);?>
</a>
</div>
<div class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”li-dec\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>
<p class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”dec-name\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>
<a href=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”https://www.wpzt.net/<?php%20echo%20get_author_posts_url(%20$fensi->ID);%20?>/?userid=<?php%20echo%20$fensi->ID;?>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” target=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”_blank\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”dec-name-link\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”><?php echo $fensi->nickname;?></a>
</p>
<p class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”dec-sub\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>
<span class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”dec-fans\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>粉丝 <?php echo get_wpdiary_bguanzhu_count($fensi->ID);?></span>
</p>
</div>
<?php
$meta = get_user_meta(get_current_user_id(),\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,true);
$user = $fensi->ID;
if($meta){
$guanzhu = explode(\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,get_user_meta(get_current_user_id(),\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’guanzhu\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\’,true));
}else{
$guanzhu = array();
}
if(in_array($user,$guanzhu)){?>
<a href=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”javascript:;\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” user=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”<?php echo $fensi->ID;?>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”addfollow sp-mod-button\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” title=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”取消关注\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>已互关</a>
<?php }else{?>
<a href=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”javascript:;\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” user=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”<?php echo $fensi->ID;?>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” class=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”addfollow sp-mod-button\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\” title=\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”关注他\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\”>关注他</a>
<?php }?>
</li>
<?php } ?>