WordPress插件开发：表单提交后重定向至新创建文章的问题及解决方案

Hey Colin, let's tackle those two issues with your WordPress post-creation plugin. I'll break down straightforward solutions for both the permalink passing problem and the blank page issue when using exit() after redirects.

Problem 1: Getting the New Post's Permalink & Passing It to Your Init Function #

Right now, your create_post() and myInit() functions are operating independently, which is why you can't access the new post ID in myInit(). The cleanest fix isn't using sessions—it's restructuring your code to run create_post() directly inside myInit() once validation passes, so you can grab the post ID immediately.

Here's the core idea:

• Modify create_post() to return the new post ID ($pid) once the post is successfully created.
• In myInit(), after validation clears, call create_post() and store the returned ID. Then use that ID to generate the permalink for the redirect.

Problem 2: Blank Page When Using exit() After Redirect #

Using PHP's native header() function can cause issues in WordPress because hidden output (like whitespace from theme/plugin files) might be sent before your redirect runs. WordPress has a built-in wp_redirect() function that handles output buffering properly, which avoids this blank page problem. Always pair wp_redirect() with exit; to stop further code execution—this is safe and recommended when using WordPress's redirect tool.

Modified Code Example #

I've updated your code with these fixes, plus some additional bug fixes (like the missing $post_type definition):

// Modified create_post() to return the new post ID
function create_post(){
    if(!is_user_logged_in()) {
        echo "<h2 style='text-align:center;'>User must be login for add post!</h2>";
        return false; // Return false if user isn't logged in
    }

    if(isset($_POST['ispost'])) {
        global $current_user;
        get_currentuserinfo();
        $user_id = $current_user->ID;

        $post_title = $_POST['title'];
        $post_content = $_POST['sample_content'];
        $category = $_POST['category'];
        // Fixed: Define your post type (adjust to your custom type if needed)
        $post_type = 'post';

        $new_post = array(
            'post_title' => $post_title,
            'post_content' => $post_content,
            'post_status' => 'publish',
            'post_type' => $post_type,
            'post_category' => $category
        );
        
        $pid = wp_insert_post($new_post);
        if(!$pid) return false; // Return false if post creation fails

        add_post_meta($pid, 'meta_key', true);

        // Handle file uploads
        if (!function_exists('wp_generate_attachment_metadata')) {
            require_once(ABSPATH . "wp-admin" . '/includes/image.php');
            require_once(ABSPATH . "wp-admin" . '/includes/file.php');
            require_once(ABSPATH . "wp-admin" . '/includes/media.php');
        }

        $attach_id = 0;
        if ($_FILES) {
            foreach ($_FILES as $file => $array) {
                if ($_FILES[$file]['error'] !== UPLOAD_ERR_OK) {
                    // Optional: Add error handling here
                    continue;
                }
                $attach_id = media_handle_upload( $file, $pid );
            }
        }

        if ($attach_id > 0) {
            update_post_meta($pid, '_thumbnail_id', $attach_id);
        }

        return $pid; // Return the new post ID to the caller
    }
    return false;
}

add_action('init', 'myInit');
function myInit() {
    if (isset($_POST['ispost'])) {
        $errors = myFormValidation();
        if (empty($errors)) {
            // Call create_post() and get the new post ID
            $new_post_id = create_post();
            if($new_post_id) {
                // Use WordPress's wp_redirect instead of raw header()
                wp_redirect(get_permalink($new_post_id));
                exit; // This is safe now with wp_redirect()
            } else {
                // Handle post creation failure
                echo "<h2 style='text-align:center;'>Failed to create post!</h2>";
            }
        } else {
            // Display validation errors
            foreach($errors as $error) {
                echo "<p style='color:red;'>$error</p>";
            }
        }
    }
}

Key Fixes Explained: #

1. Permalink Passing: By calling create_post() directly in myInit(), we get the $new_post_id immediately—no sessions needed. This is the most efficient and WordPress-standard approach.
2. Redirect & Exit Issue: Switched from header() to wp_redirect(), which manages output buffering to prevent accidental early output that causes blank pages. Adding exit; after wp_redirect() is correct here—it stops any further code from running, which is necessary for a clean redirect.
3. Other Improvements: Added a definition for $post_type (it was missing in your original code), added error checks for post creation failure, and cleaned up file upload handling.

Quick Security Note: #

Make sure your myFormValidation() function properly sanitizes and validates all user input (like $_POST['title'] and file uploads) to avoid security risks like SQL injection or malicious file uploads.

内容的提问来源于stack exchange，提问作者Colin