Javascript Online Quiz

Following quiz provides Multiple Choice Questions (MCQs) related to Javascript Framework. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the quiz.

Q 1 - Which of the following is true about variable naming conventions in JavaScript?

A - JavaScript variable names must begin with a letter or the underscore character.

B - JavaScript variable names are case sensitive.

C - Both of the above.

D - None of the above.

Answer : C

Explanation

Both of the above options are correct.

Q 2 - Can you pass a anonymous function as an argument to another function?

A - true

B - false

Answer : A

Explanation

Yes! An anonymous function can be passed as an argument to another function.

Q 3 - Which built-in method calls a function for each element in the array?

A - while()

B - loop()

C - forEach()

D - None of the above.

Answer : C

Explanation

forEach() method calls a function for each element in the array.

Q 4 - Which built-in method returns the calling string value converted to lower case?

A - toLowerCase()

B - toLower()

C - changeCase(case)

D - None of the above.

Answer : A

Explanation

toLowerCase() method returns the calling string value converted to lower case.

Q 5 - Which of the following function of Number object defines how many total digits to display of a number?

Answer : D

Explanation

toPrecision() − Defines how many total digits (including digits to the left and right of the decimal) to display of a number.

Q 6 - Which of the following function of String object returns the index within the calling String object of the last occurrence of the specified value?

Answer : A

Explanation

lastIndexOf() − Returns the index within the calling String object of the last occurrence of the specified value, or -1 if not found.

Q 7 - Which of the following function of String object returns the calling string value converted to upper case?

A - toLocaleUpperCase()

B - toUpperCase()

C - toString()

D - substring()

Answer : B

Explanation

toUpperCase() − Returns the calling string value converted to upper case.

Q 8 - Which of the following function of String object causes a string to be displayed as a subscript, as if it were in a <sub> tag?

Answer : D

Explanation

sub() − Causes a string to be displayed as a subscript, as if it were in a <sub> tag.

Q 9 - Which of the following function of Array object applies a function simultaneously against two values of the array (from left-to-right) as to reduce it to a single value?

Answer : C

Explanation

reduce() − Applies a function simultaneously against two values of the array (from left-to-right) as to reduce it to a single value.

Q 10 - Which of the following function of Array object applies a function simultaneously against two values of the array (from right-to-left) as to reduce it to a single value?