小小面試題
a的值
var a ;
if(a){
console.log('aa')
let a = 20
} else {
console.log('bb')
let a = 30
}
console.log(a)
刪除span 標籤
<div id="box">
box
<span>span</span>
</div>
<script>
var box = document.querySelector('#box');
var span = document.querySelector('span');
</script>