bg1 在绑定时，是不是el 后面的名称+‘-bind’
<div id="mount-point" v-bind:id="bg1">
<div id="bg">
<button type="button" v-on:click="dian()">点击{{ (count + 1) }}</button>
</div>
</div>
<script>
new Vue({
el: '#mount-point',
data: {
bg1: 'mount-point-bind',
count: 0
},
methods: {
dian: function () {
this.count ++
}
}
})
</script>
