Page 203 - Web Applications (803) Class 12
P. 203
for (i=0;i<fruits.length;i++)
document.write(fruits[i]+"<br>");
</script>
</font>
</body>
</html>
Output of the preceding program is as follows:
In the above example, the for loop uses the counter ‘i’ as index value to access each element.
If we try accessing a non-existent array index, we get undefined
Example:
typeof fruits[20]
Output: undefined
3.11 OBJECTS IN JAVASCRIPT
In JavaScript, almost everything is an object with the exception of six things: null, undefined, strings, numbers,
Booleans, and symbols. These are known as primitive types. An object is anything that isn’t a primitive value.
This covers constructors, functions, and arrays. Yes! we will see later in the chapter, objects also include
functions and arrays.
In terms of concept, objects are the same across all programming languages. They represent entities from
the outside world that we want to express in our programs through properties, and methods. For instance,
your object will include properties like name, age, address, id, etc., as well as methods like updateAddress,
updateName, etc., if it is a student.
Consider an object in JavaScript as a list of items, each of which is a property or method that is kept as a key-
value pair in memory. For example:
const student = {Name : "Uma", age : 15, Address : "Green Park" };
Object Key Value
In JavaScript, the named values are called properties.
Property Value
Name Uma
Age 15
Address Green Park
Web Scripting—JavaScript 201

