·用于设置事件只会触发一次。

    <!DOCTYPE html> <html lang=“en”> <head> <meta charset=“UTF-8”> <meta name=“viewport” content=“width=device-width, initial-scale=1.0”> <title>Document</title> </head> <body> <div id=“app”> <button @click=“fn”>按钮1</button> <button @click.once=“fn”>按钮2</button> </div> <script src=“lib/vue.js”></script> <script> new Vue({ el: ‘#app’, data: { }, methods: { fn () { console.log(‘按钮被点击了’); } } }) </script> </body> </html>