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JavaScript JavaScript and the DOM Getting a Handle on the DOM Select Elements by Class Name

Posted by Alex Hort-Francis
Alex Hort-Francis
12,924 Points

A phrase to remember for...of vs for...in

"For items 'of' a list, for keys 'in' a chest."

  • For...of = arrays (a list of items)
  • For...in = objects (key-value pairs)

2 Answers

Jonathan Grieve
MOD
Jonathan Grieve
Treehouse Moderator 91,253 Points
Jonathan Grieve
Jonathan Grieve
Treehouse Moderator 91,253 Points

A Very useful tip. Bookmark this page if you found this helpful. :)

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

Since "for...in" is quite commonly also used with arrays (maybe even more than "for...of"), I've always found it helpful to remember "'in' for 'index'":

  • for...in :point_left: for the in‍dex (or property name in an object) instead of the items themselves