对 Drupal 7 感到困惑 - 通过 hook_form_alter 添加 user_profile_form #validation 回调

Question

我已经搜索、阅读和重读。我什至将测试模块剥离到最基本的元素。

我认为这段代码应该可以工作，但从未调用过验证回调。我将回调添加到表单，但它在接下来的步骤中消失了。

最终，我的目标是 "validate" 提交用户名，以满足特定业务 objective。我在添加表单验证回调时遇到了困难，但我相信一旦克服了这个障碍，其余的功能就很简单了。

比我聪明的人能给我指明正确的方向以正确添加验证回调吗？

<?php
/*
    Implements hook_form_alter();
*/
function mymod_form_alter($form, $form_state, $form_id) {
    // catch the user profile form.
    if('user_profile_form' == $form_id) {
        // set debug message
        drupal_set_message(t('adding validation callback in hook_form_alter()...'), 'warning');
        // add a validation callback
        $form['#validate'][] = 'mymod_user_profile_form_validate';
    }
}

/*
    Implements hook_form_<form_id>_alter();
    If mymod_form_alter() was successful, I wouldn't need this hook, it's just here for verification.
*/
function mymod_form_user_profile_form_alter($form, $form_state, $form_id) {
    // check to see if our validation callback is present
    if(!in_array('mymod_user_profile_form_validate', $form['#validate'])) {
        // our validatiation callback is not present
        drupal_set_message(t('The validation callback is missing from #validate in hook_form_[form_id]_alter()'), 'error');
        // since it's not there, try re-adding it?
        $form['#validate'][] = 'mymod_user_profile_form_validate';
    } else {
        // We should see this message, but don't.
        drupal_set_message(t('The validation callback exists!'), 'status');
    }
}

/*
    ?? Implements hook_form_validate(); (or not...) ??
*/
function mymod_user_profile_form_validate($form, $form_state) {
    // why is mymod_user_profile_form_validate() never called??
    drupal_set_message(t('Validation callback called! Whoopee! Success!'), 'status'); // This never happens!

    // if this was working, we would do a bit of logic here on the username.  
    //for this test, let's assume we want to return an error on the username field.
    form_set_error('name', t('Blah, blah, blah, something about your username...'));
}

Answer 1

变量 $form 和 $form_state 应该是 passed by reference 这样你的钩子函数就可以实际修改它们（否则函数只是得到一个副本）。

您需要在函数签名中使用在变量参数之前添加的 &（与号）符号：

function mymod_form_alter(&$form, &$form_state, $form_id) {
  # $form is referenced from the global scope using '&' symbol
  $form['#validate'][] = 'mymod_user_profile_form_validate';
}

对 Drupal 7 感到困惑 - 通过 hook_form_alter 添加 user_profile_form #validation 回调

Stumped on Drupal 7 - adding user_profile_form #validation callback via hook_form_alter

drupal-7

hook-form-alter

drupal-form-validation