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JavaScript AJAX Basics (retiring) Programming AJAX Parsing JSON Data

Pitrov Secondary
Pitrov Secondary
5,121 Points
Posted by Pitrov Secondary
Pitrov Secondary
5,121 Points

What is typeof?

at 5:00 you can see that he writes typeof and it consoled "string" What is typeof?

3 Answers

Antti Lylander
Antti Lylander
9,686 Points
Antti Lylander
Antti Lylander
9,686 Points

It's an operator that you can use to check the type of any object. String, number, function, object etc.

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/typeof

Daan Schouten
Daan Schouten
14,454 Points
Daan Schouten
Daan Schouten
14,454 Points

Typeof literally returns the type of the variable after it. So 

console.log(typeof 43);

is going to return number. It's often used in debugging or conditional statements, because it can indicate where your code is breaking or taking unexpected input.