<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>JSDom获取图层节点</title>
</head>
<body>
<script type="text/javascript">
function getUsername() {
var dom=document.getElementById("username");
var name=dom.value;
alert(name);
}
</script>
<input type="text" id="username">
<input type="button" value="获取用户名" onclick="getUsername()">
</body>
</html>
原文：https://www.cnblogs.com/god1/p/12114650.html