VUE里面的{{}}符合可以书写JS表达式，但是不可以书写语句。例子：
<!DOCTYPE html> <html> <head> <title>VUE hello world</title> <script src="https://unpkg.com/vue/dist/vue.js"></script> <style> #simple{ margin-left: 100px; margin-top: 100px; width: 100px; height: 100px; background-color: #00a9a7; } </style> </head> <body> <div id="simple"> <p>{{name}}</p> <p>{{isShow ? "show" : "hide"}}</p> <p>{{number1 + number2}}</p> </div> <script> var simpleID = new Vue({ el:"#simple", data:{ name : "hello world", isShow : false, number1: 10, number2: 20 } }) simpleID.number2 = 30; </script> </body> </html>