在我的插件的一个短代码中，我在提交帖子的同时即时处理用户登录/注册。所以整个事情都是在短代码中发生的，比如：

<?php
function this_shortcode() {
    ob_start();
    //if isset(login)... process login, get $user_id
    //else if isset(registration)... process registration, get $user_id
    //else if already registered, get $current_user->ID as $user_id

    /**
     * if !empty($user_id){
     *  $p_id = wp_insert_post();
     *  if !empty($p_id) {
     *      echo success;
     *      **I NEED ONLY WHEN THE REDIRECTION SHOULD TAKE PLACE**
     *  } else {
     *      echo error;
     *  }
     * } else {
     * }
     */

    <form>
       <!-- registration/login + post insertion form here -->
    </form>

    return ob_get_clean();
}
add_shortcode( \'my-shortcode\', \'this_shortcode\' );

我已经知道了，wp_redirect() 不是从短代码重定向的正确方法。所以，我想做的是：

function project_registration_login_redirection(){
    global $post;
    if( has_shortcode( $post->post_content, \'my-shortcode\' ) ) {
        if ( isset( $_POST[\'my_submit\'] ) ) {
            wp_redirect( home_url(\'/that-page\') );
            exit();
        }
    }
}
add_action( \'template_redirect\', \'project_registration_login_redirection\' );

但很明显，这一个在没有任何检查的情况下重定向，即使表单验证在那里显示错误wp_insert_post() 正在返回空。

How can I process the form somewhere, but do the redirection only when the form returns a valid feedback?

我试过：

global $post, $p_id;
if ( isset( $_POST[\'my_submit\'] ) && !empty( $p_id ) ) {

但它不起作用。

function project_registration_login_redirection(){

    if ( !isset( $_POST[\'my_submit\'] ) ) {
        return;
    }

    // form validation here
    global $errors; // a global var so you can show errors on your form if any

    // I usually have a seperate validation class but you may do it different way.
    // this method is useful to feed mock array for testing purpose
    $validator = new My_Form_validator();
    $errors = $validator->validate($_POST);

    if(!empty($errors){
        return;
    }

    // no error found

    $data = $validator->get_data();
    // process form data here

    wp_redirect(home_url(\'that-page\'));
    exit;

}
add_action( \'template_redirect\', \'project_registration_login_redirection\' );