JavaScript切换类
不确定切换是如何工作的。当我点击按钮时,背景如何变回灯光主题,而脚本甚至没有指定变回灯光主题?这是JavaScript切换类,javascript,Javascript,不确定切换是如何工作的。当我点击按钮时,背景如何变回灯光主题,而脚本甚至没有指定变回灯光主题?这是document.body.classList.toggle('dark-theme') 如果该类存在,则将其删除。如果该类不存在,则添加该类 您的按钮将HTML从 'use strict' const switcher = document.querySelector('.btn'); console.log(switcher); switcher.addEventListener('clic
document.body.classList.toggle('dark-theme')代码>
如果该类存在,则将其删除。如果该类不存在,则添加该类
您的按钮将HTML从
'use strict'
const switcher = document.querySelector('.btn');
console.log(switcher);
switcher.addEventListener('click', function() {
document.body.classList.toggle('dark-theme');
let className = document.body.className;
if (className == "light-theme") {
this.textContent = "Dark";
}
else {
this.textContent = "Light";
}
});
这意味着如果元素具有暗主题
和亮主题
,暗主题
的规则将覆盖由亮主题
应用的任何重复样式
.light-theme {
/* rules */
}
.dark-theme {
/* rules */
}
主题
黑暗的
“严格使用”
const switcher=document.querySelector('.btn');
控制台日志(交换机);
switcher.addEventListener('click',function(){
document.body.classList.toggle('dark-theme');
document.body.classList.toggle('light-theme');
让className=document.body.className;
如果(类名==“灯光主题”){
this.textContent=“黑暗”;
}
否则{
this.textContent=“Light”;
}
});
<body class="light-theme dark-theme">
.light-theme {
/* rules */
}
.dark-theme {
/* rules */
}
<!doctype html>
<html>
<head>
<meta charset="UTF-8">
<title>Theme</title>
</head>
<body class="light-theme">
<div>
<button type="button" class="btn">Dark</button>
</div>
<script type="text/javascript">
'use strict'
const switcher = document.querySelector('.btn');
console.log(switcher);
switcher.addEventListener('click', function() {
document.body.classList.toggle('dark-theme');
document.body.classList.toggle('light-theme');
let className = document.body.className;
if (className == "light-theme") {
this.textContent = "Dark";
}
else {
this.textContent = "Light";
}
});
</script>
</body>
</html>