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JavaScript React Basics (2018) Introducing Props Iterating and Rendering with map()

Posted by Nigel Msipa
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Nigel Msipa
Full Stack JavaScript Techdegree Student 12,060 Points

why use map as opposed to forEach?

I'm wondering why use map as opposed to forEach?

1 Answer

Peter Vann
Peter Vann
36,427 Points

Hi Nigel!

The primary difference is that map returns an array as a value (the transformed original array) where ForEach returns 'undefined':

And map can be easily daisy-chained with other ES6 array functions (such as filter, sort, reduce, etc.).

More info:

https://www.freecodecamp.org/news/4-main-differences-between-foreach-and-map/

https://codeburst.io/javascript-map-vs-foreach-f38111822c0f

https://stackoverflow.com/questions/34426458/javascript-difference-between-foreach-and-map

I hope that helps.

Stay safe and happy coding!

Nigel Msipa
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Nigel Msipa
Full Stack JavaScript Techdegree Student 12,060 Points

Thanks a lot, that makes a lot of sense!

Chris Adams
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Chris Adams
Front End Web Development Techdegree Graduate 29,423 Points

Really helpful comment Peter, thank you!