Javascript 手风琴中的If语句
如果最大高度=0,if语句如何打开和关闭此手风琴Javascript 手风琴中的If语句,javascript,if-statement,Javascript,If Statement,如果最大高度=0,if语句如何打开和关闭此手风琴 var accordions = document.getElementsByClassName("accordion"); for (var i = 0; i < accordions.length; i++) { accordions[i].onclick = function() { this.classList.toggle('is-open'); var content = this.nextElement
var accordions = document.getElementsByClassName("accordion");
for (var i = 0; i < accordions.length; i++) {
accordions[i].onclick = function() {
this.classList.toggle('is-open');
var content = this.nextElementSibling;
if (content.style.maxHeight) {
content.style.maxHeight = null;
} else {
content.style.maxHeight = content.scrollHeight + "px";
}
}
}
var accordions=document.getElementsByClassName(“accordion”);
对于(变量i=0;i
这是HTML代码
<div class="container">
<h1>Accordions</h1>
<button class="accordion">Accordian #1</button>
<div class="accordion-content">lorem</div>
<button class="accordion">Accordian #2</button>
<div class="accordion-content">lorem</div>
<button class="accordion">Accordian #3</button>
<div class="accordion-content">lorem</div>
</div>
手风琴
手风琴1
洛勒姆
手风琴2
洛勒姆
手风琴3
洛勒姆
如果(content.style.maxHeight)
相当于:
if(content.style.maxHeight==true)
在代码中,如果content.style.maxHeight
的值为空字符串(“”
),则条件为false
,因为空字符串在JavaScript中是错误的
其他一些虚假价值观:
if(false)
if(null)
if(undefined)
if(0)
if(NaN)
if('')
if("")
您的问题是什么?
console.log(content.style.maxHeight)
explain if语句在这段代码中?此if语句中没有条件。content.style.maxheight=null如何关闭内容?@MostafaKhan,“可以关闭内容”是什么意思null
计算结果为false
。谢谢@Mamun,我得到了答案