点击按钮有前进后退效果
<!DOCTYPE html>
<html lang="en">
<script>
console.log(window.history);
//在地址栏加上?id=数字，会发现控制台的长度变化
console.log(window.screen.width);
console.log(window.screen.height);
alert(window.document);
</script>
<head>
<meta charset="utf-8">
</head>
<body>
<input type="button" value="前进" onclick="javascript:window.history.forward();" />
<input type="button" value="后退" onclick="javascript:window.history.back();" />
</body>
</html>