Trivia On JavaScript: MCQ Quiz

8 Questions | By Akshayswaroop | Updated: Mar 22, 2022 | Attempts: 544

Questions

Settings

Create your own Quiz

Questions and Answers

1.

What does the below line do considering it as the first line in your javascript file (function(){alert(this)})();
- A.
  
  Nothing happens
- B.
  
  I will see an error
- C.
  
  I will see an alert with undefined value
- D.
  
  I will see an alert with null value
- E.
  
  I will see an alert with not null value
2.
1. <input type="button" value="Button 1" id="btn1" />
2. <input type="button" value="Button 2" id="btn2" />
3. <input type="button" value="Button 3" id="btn3" onclick="buttonClicked();"/>
5. <script type="text/javascript">
6. function buttonClicked(){
7. var text = (this === window) ? 'window' : this.id;
8. alert( text );
9. }
10. var button1 = document.getElementById('btn1');
11. var button2 = document.getElementById('btn2');
13. button1.onclick = buttonClicked;
14. button2.onclick = function(){ buttonClicked(); };
15. </script>
- A.
  
  Clicking on button 3 displays btn3
- B.
  
  Clicking on button 3 displays null
- C.
  
  Clicking on button 3 displays undefined
- D.
  
  Clicking on button 3 displays something else
3.

Apply or call method can be used to override the value of this.
- A.
  
  True
- B.
  
  False
4.

When used as a constructor, like a new MyFunction(), the value of this will be a brand new object provided by the JavaScript runtime. If we don't explicitly return anything from that function, this will be considered its return value.
- A.
  
  True
- B.
  
  False
5.

When you create a plain Object, JavaScript will automatically assign a Prototype to each of these objects. This prototype will be Object.prototype.
- A.
  
  True
- B.
  
  False
6.

The prototype for "hi" is String.Prototype , and the prototype for String.Prototype is Object.Prototype
- A.
  
  True
- B.
  
  False
7.

Function Employee() { } Employee.ShowAge = function() { alert("sss"); } This adds a static method to the Employee function which would not be available to the objects of Employee function
- A.
  
  True
- B.
  
  False
8.

Employee.prototype.constructor would be Employee be default. This needs to be explicitly set in the following scenario otherwise it would be Employee for Manager.constructor.prototype Manager.prototype = new Employee(); Manager.constructor.prototype = Manager;
- A.
  
  True
- B.
  
  False