Thinkphp 3.2 添加 验证码 如何添加。

<?php
namespace Home\Controller;
use Think\Controller;
class BookController extends Controller {

    public function verify_c(){
        $Verify = new \Think\Verify();
        $Verify->fontSize = 18;
        $Verify->length   = 4;
        $Verify->useNoise = false;
        $Verify->codeSet = ‘0123456789‘;
        $Verify->imageW = 130;
        $Verify->imageH = 50;
        //$Verify->expire = 600;
        $Verify->entry();
    }
  
   
    public function img(){
       $this->display();
    }

}

<script type="text/javascript" src="__PUBLIC__/js/jquery2.0.3.min.js"></script>
<p class="top15 captcha" id="captcha-container">
    <input name="verify" width="50%" height="50" class="captcha-text" placeholder="验证码" type="text">
    <img width="100" class="left15" height="50" alt="验证码" src="{:U(‘Home/Book/verify_c‘,array())}" title="点击刷新">
</p>
        <script type="text/javascript">
            $(function(){
                var captcha_img = $(‘#captcha-container‘).find(‘img‘);
                var verifyimg = captcha_img.attr("src");
                captcha_img.attr(‘title‘, ‘点击刷新‘);
                captcha_img.click(function(){
                    if( verifyimg.indexOf(‘?‘)>0){
                        $(this).attr("src", verifyimg+‘&random=‘+Math.random());
                    }else{
                        $(this).attr("src", verifyimg.replace(/\?.*$/,‘‘)+‘?‘+Math.random());
                    }
                });
            })
        </script>