Explore topic-wise MCQs in Javascript.

This section includes 12 Mcqs, each offering curated multiple-choice questions to sharpen your Javascript knowledge and support exam preparation. Choose a topic below to get started.

1.

YOU_CAN_REFRESH_THE_WEBPAGE_IN_JAVASCRIPT_BY_USING?$

A. window.reload
B. location.reload
C. window.refresh
D. page.refresh
Answer» C. window.refresh
Discussion
2.

THE_OBJECT_WHOSE_PROPERTIES_ARE_INHERITED_BY_ALL_INSTANCES_OF_THE_CLASS,_AND_PROPERTIES_WHOSE_VALUES_ARE_FUNCTIONS_BEHAVING_LIKE_INSTANCE_METHODS_OF_THE_CLASS,_IS?$

A. Instance object
B. Constructor object
C. Destructor object
D. Prototype object
Answer» E.
Discussion
3.

You can refresh the webpage in JavaScript by using$

A. window.reload
B. location.reload
C. window.refresh
D. page.refresh
Answer» C. window.refresh
Discussion
4.

The object whose properties are inherited by all instances of the class, and properties whose values are functions behaving like instance methods of the class, i?

A. Instance object
B. Constructor object
C. Destructor object
D. Prototype object
Answer» E.
Discussion
5.

How is the render time calculated?

A. Date.Now()
B. Date.Now() – performance.timing.domLoading
C. performance.domLoading
D. Date.Now() – performance.domLoading
Answer» C. performance.domLoading
Discussion
6.

What is the purpose of the domLoading attribute?

A. Document exists
B. Document can load
C. Document has loaded
D. Document begins to load
Answer» E.
Discussion
7.

Which is the method used to add an event listener?

A. addEventListener()
B. addListener()
C. addEvent(Listener)
D. addListener(Event)
Answer» B. addListener()
Discussion
8.

Which of the following is an attribute to the script object?

A. onclick
B. onload
C. onshow
D. all of the mentioned
Answer» C. onshow
Discussion
9.

What is the result when the showPerformanceMetrics() is called before loading the remote script?

A. Throws an exception
B. Throws an error
C. It will load by itself
D. None of the mentioned
Answer» C. It will load by itself
Discussion
10.

What are the parameters of the attachEvent function?

A. Function
B. Function, Event
C. Event, Function
D. Event
Answer» D. Event
Discussion
11.

Where is the external JavaScript placed in the case of lazy loading?

A. After <b>window.onload</b> event
B. Before <b>window.onload</b> event
C. All of the mentioned
D. None of the mentioned
Answer» B. Before <b>window.onload</b> event
Discussion
12.

What is the purpose of lazy loading?

A. Immediate loading is necessary
B. Loading under command
C. Immediate loading is not necessary
D. None of the mentioned
Answer» D. None of the mentioned
Discussion