第一个页面(login.html):
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<form action="index.html">
用户名<input type="text" name="uname">
<input type="submit" value="登录">
</form>
</body>
</html>
第二个页面(index.html):
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div></div>
<script>
console.log(location.search);
//1.先去掉? substr('起始的位置',截取几个字符);
var params = location.search.substr(1);
console.log(params);
//2.利用=把字符串分割为数组 split('=');
var arr = params.split('=');
console.log(arr);
var div = document.querySelector('div');
//3.把数据写入div中
div.innerHTML = arr[1] + '欢迎您';
</script>
</body>
</html>