<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<div id ='id1'>id1</div>
<form id='form' action="/check/" method="get">
<input id='age' type="text"/>
<input onclick="DoSubmit()" type="button" value="button"/>
</form>
<script type="text/javascript">
var obj=document.getElementById('id1');
obj.innerText='change';
console.log(obj.innerText);
function DoSubmit(){
var age = document.getElementById("age");
if(age.value.trim().length > 0){
document.getElementById('form').submit();
}else{
alert('no key.....');
}
}
</script>
</body>
</html>
