Data Type in JavaScript
JavaScript has five primitive data type.
1 Number
2 String
3 Boolean
4 Undefined
5 Null
Any data type other than above 5 types is called object.
In javascript there are two types to object.
- Build in object
- Custom object
Build in Object : Examples include array, date etc. In below example we have create the object of date by using date constructor.
var date= new Date();
alert(date.getDate);
alert(date.getFullYear);
Custom objects : In JavaScript we don't have classes. We use function instead of classes.
In JavaScript there are two ways to create a custom object.
1. Constructor function
2. Literal notation
Constructor Function
<script type="text/javascript">
function Student(firstName, lastName)
{
this.firstName = firstName;
this.lastName = lastName;
this.getFullName = function ()
{
return this.firstName + " " + this.lastName;
}
}
var student= new Student("Jitendra", "Kachhi");
document.write("First Name :" + student.firstName + "<br/>");
document.write("Last Name : " + student.lastName + "<br/>");
document.write("Full Name :" + student.getFullName() + "<br/>");
</script>
literal Notation
<script type="text/javascript">
var student=
{
firstName: "Jitendra",
lastName: "Kachhi",
FullName: function ()
{
return this.firstName + " " + this.lastName;
}
}
document.write("FirstName = " + student.firstName + "<br/>");
document.write("LastName = " + student.lastName + "<br/>");
document.write("FullName = " + student.FullName() + "<br/>");
</script>
Note:- literal Notation will have only single object(singleton), if we want to create multiple object use Constructor Function.
Thanks you for reading.
