vue 验证码倒计时

//html
 <div class="input-div" v-show="formData.phone">
     <input type="text" class="input code" name="code" v-model.trim="formData.code" placeholder="验证码">
     <button @click="getCode(formData)" class="code-btn" :disabled="!show">
         <span v-show="show">获取验证码</span>
         <span v-show="!show" class="count">{{count}} s</span>
     </button>
</div>
//html
 <div class="input-div" v-show="form