<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>JavaScript strict mode prevent to writable object properties</title>
</head>
<body>
<script type="text/javascript">
// Press F12 - View result on Console Panel
var obj = {};
Object.defineProperties(obj, {
"pro1": {
value: 10,
writable: true // default false
},
"pro2": {
value: "Hello World!",
writable: false
}
});
console.log( obj ); // pro1: 10, pro2: "Hello World!"
obj.pro1 = 20; // works!, modify successfully
obj.pro2 = "Very nice!"; // not works!, prevent to modify
console.log( obj ); // pro1: 20, pro2: "Hello World!"
</script>
</body>
</html>
