示例

html:

<div id="app">
    <button v-on:click="show1">Button1</button>
    <button @click="show2">Button2</button>
    <button @click="show3">Button3</button>
    <div id="box">{{msg}}</div>
</div>

JS:

let vm = new Vue({
    el: "#app",
    data: {
        b1: false,
        msg: "盒子"
    },
    methods: {
        show1: function(eve) {
            console.log("show1", this, eve);
            this.msg = "this is a box1 data";
        },
        show2(eve) {
            console.log("show2", this, eve);
            this.msg = "this is a box2 data";
        },
        show3: (eve) => {
            console.log("show3", this, eve);
            this.msg = "this is a box3 data";
        }
    }
})

输出结果

发现使用箭头函数的show3的指向不是Vue对象