$form=$this->beginWidget('CActiveForm', array(
        'id'=>'contact-form',
        'enableAjaxValidation'=>true, //是否启用ajax验证
        'enableClientValidation'=>true, //是否启用客户端验证
        'clientOptions' => array(
                'validateOnSubmit'=>true, //提交时验证
                'validateOnChange'=>true, //输入框值改变时验证
               'validateOnType'=>false,   //键入时验证
        ),       
 'htmlOptions' => array('enctype'=>'multipart/form-data'),
)
);