Javascript Online Quiz

Q 1 - Which of the following is true about typeof operator in JavaScript?

A - The typeof is a unary operator that is placed before its single operand, which can be of any type.

B - Its value is a string indicating the data type of the operand.

C - Both of the above.

D - None of the above.

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

A - true

B - false

Q 3 - Which of the following is correct about callbacks?

A - A callback is a plain JavaScript function passed to some method as an argument or option.

B - Some callbacks are just events, called to give the user a chance to react when a certain state is triggered.

C - Both of the above.

D - None of the above.

Q 4 - Which built-in method reverses the order of the elements of an array?

A - changeOrder(order)

B - reverse()

C - sort(order)

D - None of the above.

Q 5 - Which of the following function of Number object returns a string value version of the current number?

A - toString()

B - toFixed()

C - toLocaleString()

D - toPrecision()

Q 6 - Which of the following function of String object extracts a section of a string and returns a new string?

A - slice()

B - split()

C - replace()

D - search()

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

A - toLocaleLowerCase()

B - toLowerCase()

C - toString()

D - substring()

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?

A - sup()

B - small()

C - strike()

D - sub()

Q 9 - Which of the following function of Array object adds one or more elements to the end of an array and returns the new length of the array?

A - pop()

B - push()

C - join()

D - map()

Q 10 - Which of the following function of Array object returns true if at least one element in this array satisfies the provided testing function?

A - reverse()

B - shift()

C - slice()

D - some()