如何在codeigniter中显示错误消息

我是codeigniter和创建将数据发送到邮件的表单的新手。现在我正在进行表单验证。我想如果任何人在没有填写表单数据的情况下点击提交按钮，那么错误应该显示在文本框中的占位符中。这是我在视图中的contact_us_view页面

<?php 
        $form=array('class'=>'contact-form default-form','id'=>'myform');
        echo form_open('success_form',$form);
        ?>
        <div class="row">
          <div class="col-md-12">
            <div class="preamble col-md-12">
              <h3>Get in touch</h3>
            </div>
          </div>
          <div class="col-md-6">
            <?php
            $name=array('placeholder'=>'Name','name'=>'name');
            echo form_input($name);
            ?>
          </div>
          <div class="col-md-6">
            <?php
            $company=array('placeholder'=>'Company','name'=>'company');
            echo form_input($company);
            ?>
          </div>
          <div class="col-md-6">
            <?php
            $number=array('placeholder'=>'Phone Number','name'=>'number');
            echo form_input($number);
            ?>
          </div>
          <div class="col-md-6">
            <?php
            $email=array('placeholder'=>'Email','name'=>'email');
            echo form_input($email);
            ?>
          </div>
          <div class="col-md-6">
            <span class="arrival calendar">
            <?php
            $arrival=array('name'=>'arrival','placeholder'=>'Arrival','data-dateformat'=>'m/d/y');
            echo form_input($arrival);
            ?>
                <i class="fa fa-calendar"></i>
            </span>
          </div>
          <div class="col-md-6">
            <span class="departure calendar">
            <?php
            $departure=array('name'=>'departure','placeholder'=>'Departure','data-dateformat'=>'m/d/y');
            echo form_input($arrival);
            ?>
               <i class="fa fa-calendar"></i>
            </span>
          </div>
          <div class="col-md-12">
            <span class="select-box" title="hotel-type">
              <select name="person" data-placeholder="Number of People">
                <option value="1">1</option>
                <option value="2">2</option>
                <option value="3">3</option>
                <option value="4">4</option>
                <option value="5">5</option>
                <option value="6">6</option>
                <option value="7">7</option>
                <option value="8">8</option>
                <option value="9">9</option>
                <option value="10">10</option>
                <option value="10+">10+</option>
              </select>
            </span>
          </div>
          <div class="col-md-12">
            <textarea placeholder="How we can help you"></textarea>
          </div>
          <div class="col-lg-md text-center">
            <button class="btn btn-transparent-white">Send Message</button>
          </div>
        </div>
      <?php echo form_close();?>

这是我在控制器中的控制器成功窗体

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
class Success_form extends CI_Controller{
    public function __construct() {
        parent::__construct();
        $this->load->library(array('session', 'form_validation', 'email'));
    }
    public function index(){
        // Set Validation Rule
        $this->form_validation->set_rules('name','Name','trim|required|xss_clean|callback_alpha_space_only','required');
        $this->form_validation->set_rules('company','Company','trim|required|xss_clean|callback_alpha_space_only');
        $this->form_validation->set_rules('number','Mobile Number','required|regex_match[/^[0-9]{10}$/]');
        $this->form_validation->set_rules('email', 'Emaid ID', 'trim|required|valid_email');
        $this->form_validation->set_rules('arrival','Arrival','trim|required|xss_clean');
        $this->form_validation->set_rules('departure','Departure','trim|required|xss_clean');
        $this->form_validation->set_rules('person','Number of Person','trim|required|xss_clean|numeric');

    //Run Validation on Form Input
    if($this->form_validation->run()==FALSE){
     // Validation fails
        $this->load->view('contact_us_view');
    }
    else{
        echo "successfully";
    }
    }
}

在不填写表格的情况下，如果有人点击提交按钮，则错误应显示在表格的占位符中。请帮我找出答案。。我尝试了很多，但没有得到解决方案。。请帮助