Arrays 数组值作为zend form select元素中的键

我有一个zend表单，在该表单中，我创建了一个选择框，如下所示：

$e = new Zend_Form_Element_Select('user_status');
$e->setLabel('Status');
$e->addMultiOptions(Model_User::$STATUS);
$e->setRequired(false);
$this->addElement($e);

public static $STATUS = array(
    1   =>  'creating user',
    2   =>  'creating book',
    3   =>  'book created',
    4   =>  'book send'
);

<select name="user_status" id="user_status">
   <option value="creating user" label="creating user">creating user</option>
   <option value="creating book" label="creating book" selected="selected">creating book</option>
   <option value="book created" label="book created">book created</option>
   <option value="book send" label="book send">book send</option>
</select>

Model_User:：$STATUS数组如下所示：

$e = new Zend_Form_Element_Select('user_status');
$e->setLabel('Status');
$e->addMultiOptions(Model_User::$STATUS);
$e->setRequired(false);
$this->addElement($e);

public static $STATUS = array(
    1   =>  'creating user',
    2   =>  'creating book',
    3   =>  'book created',
    4   =>  'book send'
);

<select name="user_status" id="user_status">
   <option value="creating user" label="creating user">creating user</option>
   <option value="creating book" label="creating book" selected="selected">creating book</option>
   <option value="book created" label="book created">book created</option>
   <option value="book send" label="book send">book send</option>
</select>

输出如下：

<select name="user_status" id="user_status">
   <option value="0" label="creating user">creating user</option>
   <option value="1" label="creating book" selected="selected">creating book</option>
   <option value="2" label="book created">book created</option>
   <option value="3" label="book send">book send</option>
</select>

现在我希望输出是这样的：

$e = new Zend_Form_Element_Select('user_status');
$e->setLabel('Status');
$e->addMultiOptions(Model_User::$STATUS);
$e->setRequired(false);
$this->addElement($e);

public static $STATUS = array(
    1   =>  'creating user',
    2   =>  'creating book',
    3   =>  'book created',
    4   =>  'book send'
);

<select name="user_status" id="user_status">
   <option value="creating user" label="creating user">creating user</option>
   <option value="creating book" label="creating book" selected="selected">creating book</option>
   <option value="book created" label="book created">book created</option>
   <option value="book send" label="book send">book send</option>
</select>

长话短说：

---

我希望数组值是zend表单中的键。如何在不更改状态数组键的情况下实现这一点。

只需预处理模型用户：：$status var

$statuses = array();
foreach (Model_User::$STATUS as $status) {
    $statuses[$status] = $status;
}

然后设置多个选项

$e->addMultiOptions($statuses);