Page 225 - Web Applications (803) Class 12
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student.age = 35;
student.Address = "Ajmer";
6. Explain the following with respect to Java script using suitable example.
i. Event handler ii. Objects
iii. Operator
Ans. i. Event Handler: The "event handler" is a command that is used to specify actions in response to an event. Eg:
onLoad, onMouseover etc.
ii. Objects: JavaScript objects are simply collections of name-value pairs. The "name" part is a JavaScript string,
while the value can be any JavaScript value including more objects. Objects are a way of organizing the
variables. The different screen elements such as Web pages, forms, text boxes, images, and buttons are treated
as objects.
iii. Operator: Operators are symbols which perform some operation on values. JavaScript operators can be used
to perform various operations such as:
Arithmetic Operators Comparison Operators
Logical Operators Relational Operators
Assignment Operators Conditional Operator
7. Define the characteristics of JavaScript. Are Java and JavaScript similar? Write the difference between them.
[CBSE Handbook]
Ans. The features of JavaScript are as follows:
The original purpose of JavaScript was DOM manipulation. Prior to the creation of JavaScript, the majority of
earlier websites were static.
In JavaScript, functions are objects. They might have methods and characteristics similar to those of another
object. Other functions may accept them as arguments.
Can manage time and date manipulations.
Though forms are constructed using HTML, JavaScript helps perform form validation.
A compiler need not be installed separately.
Java and JavaScript are not similar. The difference between the two is as follows:
Java JavaScript
Since variables in Java must be declared before being JavaScript is a loosely typed language and has less
used in a program, it is a tightly typed language. The strict rules and syntax.
type of a variable is verified at build time in Java.
Any virtual machine (JVM) or browser can run Java Only the browser can execute JavaScript code.
applications.
Java is an independent language. A web page has JavaScript that is integrated with the
HTML code on it.
8. Write JavaScript statements for the following:
i. To store date and time in a variable and then display date and time on the webpage.
ii. To search “sat” in the string “Humpty Dumpty sat on a wall” and display it on the webpage.
iii. Perform the following actions on an array col containing the following: [“red”, “green”, “blue”]
a. Add “silver” to the array col
b. Join array col to another array fruits containing [“apple”, “orange”]
c, Sort the array col
d. Display the array col in reverse
Web Scripting—JavaScript 223

