我认为您需要的是一个自定义重写规则，特别是一个自定义端点。

这将不得不住在s2member之外。

首先，将所有内容包装在一个类中：

<?php
class WPSE71804
{
    // post type key, whatever this happens to be.
    const TYPE = \'customer\';

    // endpoint mask, 2 ^ 18
    const EP = 262144;

    // key prefix, used for options
    const PREFIX = \'wpse71804_key_\';

    // container for the instance of this class
    private static $ins = null;

    public static function instance()
    {
        is_null(self::$ins) && self::$ins = new self;
        return self::$ins;
    }

    public static function init()
    {
        add_action(\'plugins_loaded\', array(self::instance(), \'_setup\'));
    }

    // add actions and such.
    public function _setup()
    {
       // we\'ll add actions here later.
    }
}

这里有一些常量，我们稍后将使用。

您需要修改post类型注册，以便在rewrite 论点

<?php
class WPSE71804
{
    // snip snip

    // add actions and such.
    public function _setup()
    {
        add_action(\'init\', array($this, \'register\'));
    }

    // register the post type
    public function register()
    {
        // rewrite is the args to pay attention to we need 
        // to set a custom endpoint mask
        register_post_type(self::TYPE, array(
            \'label\'     => __(\'Customers\', \'wpse\'),
            \'public\'    => true,
            \'rewrite\'   => array(
                \'slug\'          => \'customer\',
                \'ep_mask\'       => self::EP,
                \'with_front\'    => false,
            ),
        ));
    }
}

从那里，我们可以init 和电话add_rewrite_endpoint.

这将设置重写，以便我们可以转到yoursite.com/customers/the-post/key/some_key_here.

<?php
class WPSE71804
{
    // snip snip

    // add actions and such.
    public function _setup()
    {
        add_action(\'init\', array($this, \'register\'));
        add_action(\'init\', array($this, \'endpoint\'), 11);
    }

    // snip snip

    public function endpoint()
    {
        add_rewrite_endpoint(\'key\', self::EP);
    }
}

现在只需要template_redirect 并验证密钥。

<?php
class WPSE71804
{
    // snip snip

    public static function init()
    {
        add_action(\'plugins_loaded\', array(self::instance(), \'_setup\'));
        register_activation_hook(__FILE__, array(__CLASS__, \'activate\'));
    }

    // add actions and such.
    public function _setup()
    {
        add_action(\'init\', array($this, \'register\'));
        add_action(\'init\', array($this, \'endpoint\'), 11);
        add_action(\'template_redirect\', array($this, \'validate_key\'));
    }

    // snip snip

    public function validate_key()
    {
        // not a a singular customer page? Or have an admin user? bail.
        if(!is_singular(self::TYPE) || current_user_can(\'manage_options\'))
            return;

        if(!($_key = get_query_var(\'key\')) || !($key = self::get_key($_key)))
        {
            global $wp_query;
            $wp_query->set_404();
        }

        // if we\'re here, the key is okay, let the request go through
    }
}

创建一个好的API来使用可能也很有帮助（上面的代码使用了其中的一种方法）。

<?php
class WPSE71804
{
    // snip snip

    /********** API **********/

    // create a new key
    public static function create_key()
    {
        $k = wp_generate_password(24, false);
        self::update_key($k, \'notdone\');
        return $k;
    }

    // update a key
    public static function update_key($key, $val=\'done\')
    {
        return update_option(self::PREFIX . $key, $val);
    }

    // delete a key
    public static function delete_key($key)
    {
        return delete_option(self::PREFIX . $key);
    }

    public static function get_key($key)
    {
        return get_option(self::PREFIX . $key);
    }
}

现在你可以使用上面的类似。。。

<?php
// create a key
$k = WPSE71804::create_key();

// send mail with key here!

// after they submit the survey, you might want to make a note of that.
WPSE71804::update_key($k, \'done\');

// or maybe just delete it and revoke access to the page
WPSE71804::delete_key($k);

不确定s2member的使用效果如何，但基本上这将阻止所有前端没有键的页面访问。您可能根本不需要限制对s2member的访问。这些都是as a plugin.