通過點擊按鈕,實現背景色的循環變換



初始為紅色,點擊一次,變成藍色,第二次變成綠色,再次點擊,又變為紅色
這里用到vue的事件監聽 v-on:xxx
事件寫在methods里面
代碼部分
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <meta http-equiv="X-UA-Compatible" content="ie=edge"> <title>vue-test3</title> <script src="https://cdn.jsdelivr.net/npm/vue@2.6.10/dist/vue.js"></script> <style> .red{ background: red; } .blue{ background: blue; } .green{ background: green; } </style> </head> <body> <div id="test"> <button v-on:click="clickFun()">點擊</button> <p :class="classAttr[index]">改變背景色</p> </div> <script> const vm = new Vue({ el: '#test', data: { classAttr: ['red', 'blue', 'green'], index: 0, count: 0 }, methods: { clickFun() { // this = vm this就是vue實例對象 獲取data里的數據 this.index = ++this.count % 3 } } }) </script> </body> </html>
v-on可以簡寫成@ 效果一樣
<button @click="clickFun()">點擊</button>
