yii 验证码

在使用yii高级版做页面时，后台登陆用到了验证码，这个很简单，yii给出了示例：

1： 在LoginForm添加验证规则

public $verifyCode;

public function rules()
    {
        return [
            // username and password are both required
            [['username', 'password'], 'required'],
            // rememberMe must be a boolean value
            ['rememberMe', 'boolean'],
            ['verifyCode', 'captcha'],
            // password is validated by validatePassword()
            ['password', 'validatePassword'],
        ];
    }

2、在控制器中使用验证

public function actions()
    {
        return [
            'error' => [
                'class' => 'yii\web\ErrorAction',
            ],
            'captcha' =>  [
                'class' => 'yii\captcha\CaptchaAction',
                'height' => 49,
                'width' => 120,
                'minLength' => 4,
                'maxLength' => 4
            ],
        ];
    }

3、在页面显示验证码

<div class="code-box">
                <div class="code-input"><?= $form->field($model, 'verifyCode')->textInput(['autofocus' => true, 'placeholder'=>yii::t('common', 'verifyCode')])->label(false) ?></div>
                <div class="code-img"><?= Captcha::widget(['name'=>'captchaimg','captchaAction'=>'site/captcha','imageOptions'=>['id'=>'captchaimg', 'title'=>'换一个', 'alt'=>'换一个', 'style'=>'cursor:pointer;'],'template'=>'{image}']);?></div>
            </div>

$("#captchaimg").click(function(){
            $.ajax({
                    url: "<?=Url::to(['site/captcha', 'refresh'=>true])?>",
                    dataType: 'json',
                    cache: false,
                    success: function(data) {
                        $("#captchaimg").attr('src', data['url']);
                    }
                });
        });

然而在前端页面，由于我不想使用bootstrap，就把自带的assets文件夹删除了，而我想做在线留言功能，也需要验证码，这就需要自己去验证了

1、在控制器加入验证码

public function actions()
    {
        return [
            'captcha' =>  [
                'class' => 'yii\captcha\CaptchaAction',
                'height' => 32,
                'width' => 80,
                'minLength' => 4,
                'maxLength' => 4
            ],
        ];
    }

2、在页面显示验证码

<tr>
                          <td width="60" height="40" valign="middle" class="ly">验 证 码</td>
                          <td><input style="padding-left:2px; height:30px; width:160px; border:#CCC 1px solid; line-height:30px;" name="code" type="text" id="code" size="24">
                               <img src="<?=Url::to(['message/captcha'])?>" style="vertical-align:middle;"></td>
                        </tr>

3、验证

$code = Yii::$app->request->post('code');
        if($code == ''){
            return $this->redirect(['index']);
        }
        $captcha = $this->createAction('captcha');
        if(!$captcha->validate($code, false)){
            return $this->redirect(['index']);
        }