JavaScript Multiple choice Questions

Posted On:December 8, 2018, Posted By: Latest Interview Questions, Views: 3201, Rating :

JavaScript Multiple choice Questions and Answers for Freshers & Experienced

Dear readers, these JavaScript Questions and Answers have been designed specially to get you acquainted with the nature of questions you may encounter during your Job interview for the subject of JavaScript. As per my experience good interviewers hardly plan to ask any particular question during your Job interview, normally questions start with some basic concept of the subject and later they continue based on further discussion and what you answers:

1. JavaScript is ______ language.

a. Scripting

b. Programming

c. Both a and b

d. Application

Answer : a

MCQs on JavaScript

2. JavaScript is ______ Side scripting language.

a. Server

b. Client

c. ISP

d. Browser

Answer : d

3. The behaviour of the document elements can be defined by

a. Using document object

b. Registering appropriate event handlers

c. Using element object

d. All of the mentioned

Answer : b

4. The service(s) that enables networking through scripted HTTP requests is

a. XMLHttpResponse

b. XMLRequest

c. XMLHttpRequest

d. All of the mentioned

Answer : c

5. The HTML5 specification includes

a. Data storage

b. Graphics APIs

c. Other APIs for web apps

d. All of the mentioned

Answer : d

6. Which of the following are not advanced services?

a. Data storage

b. Networking

c. XMLHttpRequest object

d. None of the mentioned

Answer : d

7. JavaScript code between a pair of “script” tags are called

a. Non-inline

b. External

c. Referenced

d. Inline

Answer : d

8. Client-side JavaScript code is embedded within HTML documents in

a. A URL that uses the special javascript:encoding

b. A URL that uses the special javascript:stack

c. A URL that uses the special javascript:protocol

d. A URL that uses the special javascript:code

Answer : c

9. What is the programming philosophy that argues that content and behaviour should as much as possible be kept separate?

a. Unobtrusive JavaScript

b. Obtrusive JavaScript

c. Inherited JavaScript

d. Modular JavaScript

Answer : a

10. Which of the following communicates with server-side CGI scripts through HTML form submissions and can be written without the use of JavaScript?

a. Static Web Pages

b. Interactive Web Pages

c. Conditional Web Pages

d. None of the mentioned

Answer : b

11.  ______ tag is an extension to HTML that can enclose any number of JavaScript statements.

A.  <SCRIPT>

B.   <BODY>

C.  <HEAD>

D.  <TITLE>

 Ans: A

12.  How does JavaScript store dates in a date object?

A.  The number of milliseconds since January 1st, 1970

B.   The number of days since January 1st, 1900

C.  The number of seconds since Netscape's public stock offering.

D.  None of the above

 Ans: A

13.  Which of the following attribute can hold the JavaScript version?

A.  LANGUAGE

B.   SCRIPT

C.  VERSION

D.  None of the above

 Ans: A

14.  What is the correct JavaScript syntax to write "Hello World"?

A.  System.out.println("Hello World")

B.   println ("Hello World")

C.  document.write("Hello World")

D.  response.write("Hello World")

 Ans: C 

15.  Which of the following way can be used to indicate the LANGUAGE attribute?

A.  <LANGUAGE="JavaScriptVersion">

B.   <SCRIPT LANGUAGE="JavaScriptVersion">

C.  <SCRIPT LANGUAGE="JavaScriptVersion">    JavaScript statements…</SCRIPT>

D.  <SCRIPT LANGUAGE="JavaScriptVersion"!>    JavaScript statements…</SCRIPT>

 Ans: C

16.  Inside which HTML element do we put the JavaScript?

A.  <js>

B.   <scripting>

C.  <script>

D.  <javascript>

Ans: C 

17.  What is the correct syntax for referring to an external script called " abc.js"?

A.  <script href=" abc.js">

B.   <script name=" abc.js">

C.  <script src=" abc.js">

D.  None of the above

 Ans: C

18.  Which types of image maps can be used with JavaScript?

A.  Server-side image maps

B.  Client-side image maps

C.  Server-side image maps and Client-side image maps

D.  None of the above

 Ans: B

19.  Which of the following navigator object properties is the same in both   Netscape and IE?

A.  navigator.appCodeName

B.   navigator.appName

C.  navigator.appVersion

D.  None of the above

 Ans: A

20.  Which is the correct way to write a JavaScript array?

A.  var txt = new Array(1:"tim",2:"kim",3:"jim")

B.   var txt = new Array:1=("tim")2=("kim")3=("jim")

C.  var txt = new Array("tim","kim","jim")

D.  var txt = new Array="tim","kim","jim"

Ans: C 

21.  What does the <noscript> tag do?

A.  Enclose text to be displayed by non-JavaScript browsers.

B.   Prevents scripts on the page from executing.

C.  Describes certain low-budget movies.

D.  None of the above

 Ans: A

22. If para1 is the DOM object for a paragraph, what is the correct syntax to change the text within the paragraph?

A.  "New Text"?

B.  para1.value="New Text";

C.  para1.firstChild.nodeValue= "New Text";

D.  para1.nodeValue="New Text";

Ans: B 

23.  JavaScript entities start with _______ and end with _________.

A.  Semicolon, colon

B.   Semicolon, Ampersand

C.  Ampersand, colon

D.  Ampersand, semicolon

 Ans: D

24.  Which of the following best describes JavaScript?

A.  a low-level programming language.

B.   a scripting language precompiled in the browser.

C.  a compiled scripting language.

D.  an object-oriented scripting language.

 Ans: D 

25.  Choose the server-side JavaScript object?

A.  FileUpLoad

B.   Function

C.  File

D.  Date

Ans: C  

26.  Choose the client-side JavaScript object?

A.  Database

B.   Cursor

C.  Client

D.  FileUpLoad

Ans: D  

27.  Which of the following is not considered a JavaScript operator?

A.  new

B.  this

C.  delete

D.  typeof

 Ans: B 

28.  ______method evaluates a string of JavaScript code in the context of the specified object.

A.  Eval

B.   ParseInt

C.  ParseFloat

D.  Efloat

 Ans: A 

29.  Which of the following event fires when the form element loses the focus: <button>, <input>, <label>, <select>, <textarea>?

A.  onfocus

B.  onblur

C.  onclick

D.  ondblclick

 Ans: B

30.  The syntax of Eval is _______.

A.  [objectName.]eval(numeriC.

B.  [objectName.]eval(string)

C.  [EvalName.]eval(string)

D.  [EvalName.]eval(numeriC.

Ans: B 

31.  JavaScript is interpreted by ______.

A.  Client

B.   Server

C.  Object

D.  None of the above

Ans: A 

32.  Using _______ statement is how you test for a specific condition.

A.  Select

B.  If

C.  Switch

D.  For

 Ans: B

33.  Which of the following is the structure of an if statement?

A.  if (conditional expression is true) thenexecute this codeend if

B.   if (conditional expression is true)execute this codeend if

C.  if (conditional expression is true)   {then execute this code>->}

D.  if (conditional expression is true) then {execute this code}

Ans: C 

34.  How to create a Date object in JavaScript?

A.  dateObjectName = new Date([parameters])

B.   dateObjectName.new Date([parameters])

C.  dateObjectName := new Date([parameters])

D.  dateObjectName Date([parameters])

 Ans: A

35.  The _______ method of an Array object adds and/or removes elements from an array.

A.  Reverse

B.   Shift

C.  Slice

D.  Splice

 Ans: D 

36.  To set up the window to capture all Click events, we use which of the following statement?

A.  window.captureEvents(Event.CLICK);

B.   window.handleEvents (Event.CLICK);

C.  window.routeEvents(Event.CLICK );

D.  window.raiseEvents(Event.CLICK );

 Ans: A

37.  Which tag(s) can handle mouse events in Netscape?

A.  <IMG>

B.  <A>

C.  <BR>

D.  None of the above

 Ans: B

38.  ________ is the tainted property of a window object.

A.  Pathname

B.   Protocol

C.  Defaultstatus

D.  Host

 Ans: C

39.  To enable data tainting, the end user sets the _________ environment variable.

A.  ENABLE_TAINT

B.   MS_ENABLE_TAINT

C.  NS_ENABLE_TAINT

D.  ENABLE_TAINT_NS

 Ans: C

40.  In JavaScript, _________ is an object of the target language data type that encloses an object of the source language.

A.  a wrapper

B.   a link

C.  a cursor

D.  a form 

 Ans: A 

41.  When a JavaScript object is sent to Java, the runtime engine creates a Java wrapper of type ________.

A.  ScriptObject

B.  JSObject

C.  JavaObject

D.  Jobject

Ans: B 

42.  _______ class provides an interface for invoking JavaScript methods and examining JavaScript properties.

A.  ScriptObject

B.  JSObject

C.  JavaObject

D.  Jobject

 Ans: B

43.  _________ is a wrapped Java array, accessed from within JavaScript code.

A.  JavaArray

B.   JavaClass

C.  JavaObject

D.  JavaPackage

Ans:  A   

44. A ________ object is a reference to one of the classes in a Java package, such as netscape.javascript .

A.  JavaArray

B.  JavaClass

C.  JavaObject

D.  JavaPackage

 Ans: B

45.  The JavaScript exception is available to the Java code as an instance of _______.

A.  netscape.javascript.JSObject

B.  netscape.javascript.JSException

C.  netscape.plugin.JSException

D.  None of the above

Ans: B 

46. To automatically open the console when a JavaScript error occurs which of the following is added to prefs.js?

A.  user_pref(" javascript.console.open_on_error", false);

B.   user_pref("javascript.console.open_error ", true);

C.  user_pref("javascript.console.open_error ", false);

D.   user_pref("javascript.console.open_on_error", true);

Ans: D 

47.  To open a dialog box each time an error occurs, which of the following is added to prefs.js?

A.  user_pref("javascript.classic.error_alerts", true);

B.   user_pref("javascript.classic.error_alerts ", false);

C.  user_pref("javascript.console.open_on_error ", true);

D.  user_pref("javascript.console.open_on_error ", false);

 Ans: A

48.  The syntax of a blur method in a button object is _______.

A.  Blur()

B.   Blur(contrast)

C.  Blur(value)

D.  Blur(depth)

 Ans: A

49.  The syntax of capture events method for document object is _______.

A.  captureEvents()

B.   captureEvents(args eventType)

C.  captureEvents(eventType)

D.  captureEvents(eventVal)

 Ans: C

50.  The syntax of close method for document object is ________.

A.  Close(doC.

B.   Close(object)

C.  Close(val)

D.  Close()

Ans: D