<!DOCTYPE html>
<html>
<head>
<script>
function setResult()
{
document.getElementById("email").readOnly=true;
}
</script>
</head>
<body>
<form>
Email: <input type="text" id="email">
</form>
<button type="button" onclick="setResult()">设置只读</button>
</body>
</html>
