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JavaScript JavaScript Foundations Functions Return Values

Anthony Giuliano
Anthony Giuliano
9,569 Points
Posted by Anthony Giuliano
Anthony Giuliano
9,569 Points

Functions / Return Values Code Challenge

Having trouble with this one. I remember from the video that you can test if an argument is empty with a conditional like:

if(var === 'undefined')

But I don't recall going over how to test if the variable contains a string or a number.

3 Answers

J Donahue
J Donahue
30,790 Points

You would use the typeof operator to test whether a variable holds the value of a string or a number

For example:

var one = 1; var str = "String";

if (typeof one === 'number') { console.log("This is a number"); }

if (typeof str === "string") { console.log("This is a string"); }

Anthony Giuliano
Anthony Giuliano
9,569 Points
Anthony Giuliano
Anthony Giuliano
9,569 Points

Thanks for the answer! I had literally just started the video over again and caught his use of the typeof operator. Although interestingly I found that typeof array returns 'Object', which I wasn't expecting.

Thanks again.

Laura Nielsen
Laura Nielsen
7,200 Points
Laura Nielsen
Laura Nielsen
7,200 Points

Thanks this was very helpful =)