利用Vue实现计数器 

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <script src="https://unpkg.com/vue@next"></script>
    <title>Document</title>
  </head>
  <body>
    <div id="app">
      <p style="font-size: 25px;">计数器: {{ counter }}</p>
      <button @click="counter++" style="font-size: 25px;">点我</button>
    </div>

    <script>
      const app = {
        data() {
          return {
            counter: 1,
          }
        },
      }
      vm = Vue.createApp(app).mount('#app')
      vm.$watch('counter', function (nval, oval) {
        alert('计数器值的变化 :' + oval + ' 变为 ' + nval + '!')
      })
    </script>
  </body>
</html>

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posted @ 2022-04-28 15:47  wjxuriel  阅读(161)  评论(0)    收藏  举报