There are no such class variables in JavaScript. There are some frameworks out there that simulate a classical inheritance pattern, but technically it all boils down to constructor functions and prototypes.
You can do this:
PersonProto = { // the "class", or prototype
fname: "thisfname"
};
function Person() { // the constructor function
this.instanceVar = 'foo';
}Now, connect the constructor to the prototype:
Person.prototype = PersonProto;And, voilà:
var a = new Person();
alert(a.fname);A class variable is an important part of object-oriented programming (OOP) that defines a specific attribute or property for a class.
JavaScript class variables
Simple example code.
This is still a proposal and it would look as follows:
class A {
property = "value";
}BTW, when you want to access a class property (i.e. an own object property) you’ll still need to use this.property:
<!DOCTYPE html>
<html>
<body>
<script>
class A {
property = "value";
constructor() {
console.log(this.property);
}
}
var test = new A();
console.log(test.property);
</script>
</body>
</html> Output:
3 ways to define a variable in JavaScript class:
1)To define properties created using a function(), you use the ‘this’ keyword
function Apple (type) {
this.type = type;
this.color = "red";
}To instantiate an object of the Apple class, set some properties you can do the following:
var apple = new Apple('macintosh');
apple.color = "reddish";2) Using Literal Notation
var apple = {
type: “macintosh”,
color: “red”}
In this case, you don’t need to (and cannot) create an instance of the class, it already exists.
apple.color = "reddish";3) Singleton using a function
var apple = new function() {
this.type = "macintosh";
this.color = "red";
}So you see that this is very similar to 1 discussed above, but the way to use the object is exactly like in 2.
apple.color = "reddish";Source: stackoverflow.com
Do comment if you have any doubts or suggestions on this Js class topic.
Note: The All JS Examples codes are tested on the Firefox browser and the Chrome browser.
OS: Windows 10
Code: HTML 5 Version