JavaScript .prototype如何工作？
JavaScript中的对象从其原型继承属性和方法。我们通常使用new创建一个对象Object()，该对象也将从Object.prototype继承。同样，具有新对象的对象将Date()继承Date.prototype。
示例
<!DOCTYPE html>
<html>
<body>
<h2>Department Details</h2>
<p id="details"></p>
<script>
function Department(myid, name, section) {
this.id = myid;
this.name = name;
this.section = section;
}
var myDept = new Department("AKD", "Marketing", "North");
document.getElementById("details").innerHTML =
"The name and section of the Department is " + myDept.name + " and "
+ myDept.section+ " respectively.";
</script>
</body>
</html>