vue实现验证码按钮倒计时功能

站长资源 2024/11/27 佚名

2 0 1

本人最近开始尝试学习vue.js。想使用vue写一个小例子，就选择做验证码按钮倒计时功能。

上网上搜了一下，也把他们的代码试了一下，自己出了很多问题。所以，需要写一篇基础入门的文章，避免后面人采坑。

这是按照网上写的HTML页面

<div class="register-pannel" id ="register-pannel"> 
      <div class="register-l" align="center"> 
        <div class="input-group" style="width: 300px;"> 
          <input type="text" class="form-control" placeholder="邮箱/手机号/用户名" style="height: 40px;" /> 
          <span class="glyphicon glyphicon-user form-control-feedback" aria-hidden="true" /> 
        </div> 
        <br /> 
        <div class="input-group" style="width: 300px;"> 
          <input type="text" class="form-control" placeholder="密码" style="height: 40px;" /> 
          <span class="glyphicon glyphicon-lock form-control-feedback" /> 
        </div> 
        <br /> 
        <div class="input-group" style="width: 300px;"> 
          <input type="text" class="form-control" placeholder="手机号" style="height: 40px;" /> 
          <span class="glyphicon glyphicon-phone form-control-feedback" /> 
        </div> 
        <br /> 
        <div class="input-group" style="width: 300px;"> 
            <span class="register-msg-btn" v-show="show" v-on:click="getCode">发送验证码</span> 
            <span class="register-msg-btn" v-show="!show">{{count}} s</span> 
          <input type="text" class="form-control" placeholder="验证码" style="float: right; height: 40px; width: 150px;" /> 
          <span class="glyphicon glyphicon-font form-control-feedback" /> 
        </div> 
        <br /> 
        <span class="btn-register">注册</span> 
      </div>

js写成

<script> 
<span style="white-space: pre;">      </span>data(){   
<span style="white-space: pre;">      </span>return {   
<span style="white-space: pre;">        </span>show: true,   
<span style="white-space: pre;">        </span>count: '',   
<span style="white-space: pre;">        </span>timer: null,   
<span style="white-space: pre;">      </span>}  
<span style="white-space: pre;">    </span>},  
<span style="white-space: pre;">    </span>methods:{   
<span style="white-space: pre;">      </span>getCode(){    
<span style="white-space: pre;">        </span>const TIME_COUNT = 60;    
<span style="white-space: pre;">        </span>if (!this.timer) {     
<span style="white-space: pre;">          </span>this.count = TIME_COUNT;     
<span style="white-space: pre;">          </span>this.show = false;     
<span style="white-space: pre;">          </span>this.timer = setInterval(() => {     
<span style="white-space: pre;">            </span>if (this.count > 0 && this.count <= TIME_COUNT) {      
<span style="white-space: pre;">              </span>this.count--;      
<span style="white-space: pre;">            </span>} else {      
<span style="white-space: pre;">              </span>this.show = true;      
<span style="white-space: pre;">              </span>clearInterval(this.timer);      
<span style="white-space: pre;">              </span>this.timer = null;      
<span style="white-space: pre;">            </span>}     
<span style="white-space: pre;">          </span>}, 1000)     
<span style="white-space: pre;">        </span>}   
<span style="white-space: pre;">      </span>}   
<span style="white-space: pre;">    </span>} 
</script>

发现浏览器一直报错Uncaught SyntaxError: Unexpected token {

所以按照官方文档的格式，把js的结构改成

<script> 
    new Vue({ 
      el:'.register-pannel',      
      data:{    
        show:true,   
        timer:null, 
        count:'' 
      },  
      methods:{   
        getCode(){ 
          this.show = false; 
          const TIME_COUNT = 60;    
          if (!this.timer) {     
            this.count = TIME_COUNT;     
            this.show = false;     
            this.timer = setInterval(() => {     
              if (this.count > 0 && this.count <= TIME_COUNT) {      
                this.count--;      
              } else {      
                this.show = true;      
                clearInterval(this.timer);      
                this.timer = null;      
              }     
            }, 1000)     
          }   
        }   
      } 
    }); 
    </script>

于是格式是没有问题了，但是样式并没有生效。变成了另一个样子。

上网上搜了很多。

有说是js引用顺序的问题。

有说是将js写进window.onload的。试了一下，发现都不对。

后来，在官方文档中发现了el属性：为实例提供挂载元素。值可以是 CSS 选择符，或实际 HTML 元素，或返回 HTML 元素的函数。

所以改成

<script>
 new Vue({
  el:'.register-pannel', //注册div的class 
  data:{   
  show:true,  
  timer:null,
  count:''
  }, 
  methods:{  
  getCode(){
   this.show = false;
   const TIME_COUNT = 60;   
   if (!this.timer) {    
   this.count = TIME_COUNT;    
   this.show = false;    
   this.timer = setInterval(() => {    
    if (this.count > 0 && this.count <= TIME_COUNT) {     
    this.count--;     
    } else {     
    this.show = true;     
    clearInterval(this.timer);     
    this.timer = null;     
    }    
   }, 1000)    
   }  
  }  
  }
 });
</script>

效果就出来了。