夜光带你走进 前端工程师(二十八 jS )
夜光序言:
小时候,微笑是一种心情,长大后,微笑是一种表情。
正文:
<script>
function fn(a,b){
console.log(fn.length); //得到的是 函数的形参的个数
console.log(arguments); //输出[1,2]
console.log(arguments.length);
if(fn.length==arguments.length)
{
console.log(a+b);
}
else
{
console.log("sorry,形参实参个数不匹配");
}
}
fn(1,2);
</script>
//输出 因为 实参形参个数相互一致 所以输出3
console.error("sorry,形参实参个数不匹配");
//以 形参为准
函数传参显示盒子夜光
|
Var a=10,b=20;
[var a=10;
Var b=20;]
鼠标展示CSS部分夜光 |
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title></title>
<style>
#box{
height: 70px;
width: 360px;
padding-top: 360px;
border: 1px solid #ccc;
margin: 100px auto;
}
</style>
</head>
<body>
<div id="box">
</div>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title></title>
<style>
*{margin: 0;padding: 0;}
ul{list-style: none;}
#box{
height: 70px;
width: 360px;
padding-top: 360px;
border: 1px solid #ccc;
margin: 100px auto;
overflow: hidden;
background: url(韩信萌.jpeg) no-repeat;
}
#box ul{
overflow: hidden;
border-top: 1px solid #ccc;
}
#box li{
float: left;
}
</style>
</head>
<body>
<div id="box">
<ul>
<li><img src="嬴政01%20尺寸降低.jpg" alt="" width="72px"/> </li>
<li><img src="韩信特效01%20尺寸缩小.jpg" alt="" width="72px"/> </li>
<li><img src="大小姐01%20%20尺寸降低.jpg" alt="" width="72px"/> </li>
<li><img src="韩信萌.jpeg" alt="" width="72px"/> </li>
</ul>
</div>
</body>
</html>
鼠标展示JS部分夜光 |
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title></title>
<style>
*{margin: 0;padding: 0;}
ul{list-style: none;}
#box{
height: 70px;
width: 360px;
padding-top: 360px;
border: 1px solid #ccc;
margin: 100px auto;
overflow: hidden;
background: url(韩信萌.jpeg) no-repeat;
}
#box ul{
overflow: hidden;
border-top: 1px solid #ccc;
}
#box li{
float: left;
}
</style>
<script>
window.onload =function(){
var a2=document.getElementById("a2");
var box=document.getElementById("box");
a2.onmouseover=function(){
box.style.backgroundImage = "url(韩信特效01%20尺寸缩小.jpg)";
}
}
</script> // 这里才是关键
</head>
<body>
<div id="box">
<ul>
<li id="a1"><img src="嬴政01%20尺寸降低.jpg" alt="" width="72px"/> </li>
<li id="a2"><img src="韩信特效01%20尺寸缩小.jpg" alt="" width="72px"/> </li>
<li id="a3"><img src="大小姐01%20%20尺寸降低.jpg" alt="" width="72px"/> </li>
<li id="a4"><img src="韩信萌.jpeg" alt="" width="72px"/> </li>
</ul>
</div>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title></title>
<style>
*{margin: 0;padding: 0;}
ul{list-style: none;}
#box{
height: 70px;
width: 360px;
padding-top: 360px;
border: 1px solid #ccc;
margin: 100px auto;
overflow: hidden;
background: url(韩信萌.jpeg) no-repeat;
}
#box ul{
overflow: hidden;
border-top: 1px solid #ccc;
}
#box li{
float: left;
}
</style>
<script>
/* window.onload =function(){
var a2=document.getElementById("a2");
var box=document.getElementById("box");
a2.οnmοuseοver=function(){
box.style.backgroundImage = "url(韩信特效01%20尺寸缩小.jpg)";
}
}*/
window.onload=function(){
var box=document.getElementById("box");
function fn(ad,bg){
var target=document.getElementById(ad);
target.onmouseover=function(){
box.style.backgroundImage = bg;
}
}
fn("a1","url(嬴政01%20尺寸降低.jpg)"); //实参
fn("a2","url(韩信特效01%20尺寸缩小.jpg)"); //实参
fn("a3","url(大小姐01%20%20尺寸降低.jpg.jpg)"); //实参
fn("a4","url(韩信萌.jpeg.jpg)"); //实参
fn("a5","url(守约01.jpeg)"); //实参
}
</script>
</head>
<body>
<div id="box">
<ul>
<li id="a1"><img src="嬴政01%20尺寸降低.jpg" alt="" width="72px" height="72px"/> </li>
<li id="a2"><img src="韩信特效01%20尺寸缩小.jpg" alt="" width="72px" height="72px"/> </li>
<li id="a3"><img src="大小姐01%20%20尺寸降低.jpg" alt="" width="72px" height="72px"/> </li>
<li id="a4"><img src="韩信萌.jpeg" alt="" width="72px" height="72px"/> </li>
<li id="a5"><img src="守约01.jpeg" alt="" width="72px" height="72px"/> </li>
</ul>
</div>
</body>
</html>
// 这些代码 看几十遍 融会贯通