在 WordPress 中验证帖子标题和内容

Question

我打算让用户通过前端创建博客文章。 我需要确保帖子标题和内容都少于 100 个字符。

我应该把我的验证功能挂到哪个钩子上？

提前致谢。

Answer 1

此代码确保帖子标题不为空或不超过 100 个字符。 如有必要，您可以根据需要进行调整。 该代码将按如下方式工作：

• 如果您在创建新帖子时出现错误，该帖子将不会发布，它将保持自动草稿状态（不会显示在列表中）；
• 如果现有帖子更新过程中出现错误， post_title和post_status不会改变；
• 将your_custom_post_type替换为您的自定义帖子类型。

编码：

<?php

add_action('save_post_{your_custom_post_type}', 'custom_validate_post', 10, 2);

if (!function_exists('custom_validate_post')) {
    function custom_validate_post(int $post_ID, WP_Post $post): void
    {
        // Exit early if save_post is triggered when trashing the post
        if ($post->post_status === 'trash' || defined('DOING_AUTOSAVE') && DOING_AUTOSAVE) {
            return;
        }

        $errors = [];

        // Validation filters
        if (empty($post->post_title)) {
            $errors['title'] = 'The title is required';
        }

        if(strlen($post->post_title) > 100) {
            $errors['title'] = 'The title should not be longer than 100 characters';
        }

        // If we have errors lets setup some messages
        if (!empty($errors)) {
            // Save the errors as option
            update_option('post_errors', $errors);

            // admin_notice is create by a $_GET['message'] with a number that wordpress uses to
            // Display the admin message so we will add a filter for replacing default admin message with a redirect
            add_filter('redirect_post_location', function (string $location) {
                // Remove $_GET['message']
                $location = remove_query_arg( 'message', $location );

                // Add our new query sting
                $location = add_query_arg( 'custom_validation', 'failed', $location );

                // Return the location query string
                return $location;
            });
        }
    }
}

// We use this action to get the data before and after the update in order to revert the data if validation fails
add_action('post_updated', 'custom_set_old_post_data_if_error', 10, 3);

if (!function_exists('custom_set_old_post_data_if_error')) {
    function custom_set_old_post_data_if_error(int $post_ID, WP_Post $post_after, WP_Post $post_before)
    {
        // Exit early if post_updated is triggered when trashing the post
        if ($post_after->post_status === 'trash' || $post_after->post_type !== 'your_custom_post_type') {
            return;
        }

        if (empty($post_after->post_title) || strlen($post_after->post_title) > 100) {
            // We must remove this action or it will loop forever since we use wp_update_post below
            remove_action('post_updated', 'custom_set_old_post_data_if_error');


            // Set old `post_title` and `post_status` if validation fails
            wp_update_post(
                [
                    'ID' => $post_after->ID,
                    'post_title' => $post_before->post_title,
                    'post_status' => $post_before->post_status,
                ]
            );

            add_action('post_updated', 'custom_set_old_post_data_if_error');
        }
    }
}

// Add new admin message
add_action( 'admin_notices', function () {
        if (isset($_GET['custom_validation']) && $_GET['custom_validation'] === 'failed') {

        // Get the errors from the option album_errors
        $errors = get_option('post_errors');

        // Now delete the option post errors
        delete_option('post_errors');

        $display = '<div id="notice" class="error"><ul>';

        // Because we are storing as an array we should loop through them
        foreach ( $errors as $error ) {
            $display .= '<li>' . $error . '</li>';
        }

        $display .= '</ul></div>';

        // Finally echo out our display
        echo $display;

        // Add some jQuery
        ?>
        <script>
            jQuery(function($) {
                $("#title").css({"border": "1px solid red"})
            });
        </script>
        <?php
    }
});

有几件事需要注意：

• 如果回收站中有标题无效的帖子，您将无法在更改标题之前取消这些帖子；
• 如果您想将此应用于所有帖子而不是某个自定义帖子类型，请使用save_post挂钩而不是save_post_{your_custom_post_type}并从代码中删除$post_after->post_type !== 'your_custom_post_type'条件。

祝你好运！

Answer 2

尝试这个：

为此使用插件。 它会帮助你需要的。

请参考： http ://wordpress.org/plugins/post-title-validation/

或者

使用此代码。

add_action( 'admin_notices', 'custom_error_notice' );
function custom_error_notice(){
    global $current_screen, $post;
    if ( $current_screen->parent_base == 'edit' ){
        if((!$post->post_name && !$post_content) && $_GET['post']) {
            wp_redirect(admin_url('post-new.php?empty=1'));
        }
        if($_GET['empty']) echo '<div class="error"><p>Warning - Please fill up all fields correctly!</p></div>';
    }
}

• 谢谢

Answer 3

需要的钩子是 wp_insert_post_data

http://codex.wordpress.org/Plugin_API/Filter_Reference/wp_insert_post_data