Javascript Interview Questions

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

What is JavaScript?

Name some of the JavaScript features.

What are the advantages of using JavaScript?

What are disadvantages of using JavaScript?

Is JavaScript a case-sensitive language?

How can you create an Object in JavaScript?

How can you read properties of an Object in JavaScript?

How can you create an Array in JavaScript?

How to read elements of an array in JavaScript?

What is a named function in JavaScript? How to define a named function?

How many types of functions JavaScript supports?

How to define a anonymous function?

Can you assign a anonymous function to a variable?

Can you pass a anonymous function as an argument to another function?

What is arguments object in JavaScript?

How can you get the type of arguments passed to a function?

How can you get the total number of arguments passed to a function?

How can you get the reference of a caller function inside a function?

What is the purpose of 'this' operator in JavaScript?

What are the valid scopes of a variable in JavaScript?

Which type of variable among global and local, takes precedence over other if names are same?

What is callback?

What is closure?

Give an example of closure?

Which built-in method returns the character at the specified index?

Which built-in method combines the text of two strings and returns a new string?

Which built-in method calls a function for each element in the array?

Which built-in method returns the index within the calling String object of the first occurrence of the specified value?

Which built-in method returns the length of the string?

Which built-in method removes the last element from an array and returns that element?

Which built-in method adds one or more elements to the end of an array and returns the new length of the array?

Which built-in method reverses the order of the elements of an array?

Which built-in method sorts the elements of an array?

Which built-in method returns the characters in a string beginning at the specified location?

Which built-in method returns the calling string value converted to lower case?

Which built-in method returns the calling string value converted to upper case?

Which built-in method returns the string representation of the number's value?

What are the variable naming conventions in JavaScript?

How typeof operator works?

What typeof returns for a null value?

Can you access Cookie using javascript?

How to create a Cookie using JavaScript?

How to read a Cookie using JavaScript?

How to delete a Cookie using JavaScript?

How to redirect a url using JavaScript?

How to print a web page using javascript?

What is Date object in JavaScript?

What is Number object in JavaScript?

How to handle exceptions in JavaScript?

What is purpose of onError event handler in JavaScript?

What is Next ?

Further you can go through your past assignments you have done with the subject and make sure you are able to speak confidently on them. If you are fresher then interviewer does not expect you will answer very complex questions, rather you have to make your basics concepts very strong.

Second it really doesn't matter much if you could not answer few questions but it matters that whatever you answered, you must have answered with confidence. So just feel confident during your interview. We at tutorialspoint wish you best luck to have a good interviewer and all the very best for your future endeavor. Cheers :-)