set_rules()

public function submit(): void { $this->trongate_security->make_sure_allowed(); $submit = post('submit', true); if ($submit === 'Submit') { // Define validation rules for each field $this->validation->set_rules('task_title', 'Task Title', 'required|min_length[2]|max_length[255]'); $this->validation->set_rules('task_description', 'Task Description', 'required|min_length[2]'); // Run all validations if ($this->validation->run() === true) { // Validation passed - process the form $data = [ 'task_title' => post('task_title', true), 'task_description' => post('task_description', true) ]; $this->db->insert($data, 'tasks'); redirect('tasks/manage'); } else { // Validation failed - redisplay form with errors $this->create(); } } }

public function submit_registration(): void { // Username validation $this->validation->set_rules('username', 'Username', 'required|min_length[3]|max_length[50]|callback_check_username_available'); // Email validation with DNS checking $this->validation->set_rules('email', 'Email Address', 'required|valid_email'); // Password validation with confirmation $this->validation->set_rules('password', 'Password', 'required|min_length[8]|max_length[255]'); $this->validation->set_rules('password_confirm', 'Password Confirmation', 'required|matches[password]'); // Age validation $this->validation->set_rules('age', 'Age', 'required|integer|greater_than[17]|less_than[120]'); if ($this->validation->run() === true) { // Process registration... } else { $this->register(); // Redisplay with errors } }

public function submit_profile_photo(): void { // Validate uploaded image $this->validation->set_rules('profile_photo', 'Profile Photo', 'required|allowed_types[jpg,jpeg,png]|max_size[2048]|square|max_width[1000]|max_height[1000]'); if ($this->validation->run() === true) { // Process file upload... $file = $_FILES['profile_photo']; // Handle file storage... } else { $this->upload_form(); } }

public function submit(): void { // Use custom validation callback $this->validation->set_rules('username', 'Username', 'required|callback_check_username_unique'); if ($this->validation->run() === true) { // Username is unique and valid... } } /** * Custom validation callback to check username uniqueness * * @param string $submitted_username The username to validate * @return string|bool Returns error message string if invalid, true if valid */ public function check_username_unique(string $submitted_username): string|bool { $existing = $this->db->get_one_where('username', $submitted_username, 'users'); if ($existing) { return 'The {label} is already taken. Please choose another.'; } return true; }

public function submit_booking(): void { $this->validation->set_rules('start_date', 'Start Date', 'required|valid_date'); $this->validation->set_rules('end_date', 'End Date', 'required|valid_date|callback_check_date_range'); $this->validation->set_rules('check_in_time', 'Check-in Time', 'required|valid_time'); if ($this->validation->run() === true) { // Process booking... } } public function check_date_range(string $end_date): string|bool { $start = post('start_date', true); $end = post('end_date', true); if (strtotime($end) <= strtotime($start)) { return 'The {label} must be after the Start Date.'; } return true; }

// All rules must pass for validation to succeed $this->validation->set_rules('email', 'Email Address', 'required|valid_email|max_length[254]'); // If 'required' fails, other rules are still checked $this->validation->set_rules('phone', 'Phone Number', 'required|exact_length[10]|numeric'); // Combining length and comparison rules $this->validation->set_rules('price', 'Price', 'required|numeric|greater_than[0]|less_than[10000]');

<!-- In your view --> <?php echo form_open_upload('documents/submit'); echo form_label('Document'); echo form_file_select('document'); echo form_submit('submit', 'Upload'); echo form_close(); ?>

// In your controller public function submit(): void { $this->validation->set_rules('document', 'Document', 'required|allowed_types[pdf,doc,docx]|max_size[5120]'); if ($this->validation->run() === true) { // File passed validation - safe to process $file = $_FILES['document']; $destination = APPPATH . 'public/uploads/' . $file['name']; move_uploaded_file($file['tmp_name'], $destination); set_flashdata('Document uploaded successfully'); redirect('documents/manage'); } else { $this->upload_form(); } }

<!-- Display all errors at top of form --> <?= validation_errors() ?> <!-- Or display inline per-field errors --> <?php echo form_label('Email'); echo validation_errors('email'); echo form_input('email', post('email', true)); ?>