未使用ajax将Codeigniter选择框值传递给控制器

<form method="post" action="<?php echo site_url('controller_name/method_name'); ?>">
    <select name="select_box">
        <option value="option1">Option 1</option>
        <option value="option2">Option 2</option>
        <option value="option3">Option 3</option>
    </select>
    <input type="submit" value="Submit">
</form>

class Controller_name extends CI_Controller {
    public function method_name() {
        $selected_value = $this->input->post('select_box');
        
        // 进行相应的处理逻辑
    }
}