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Mastering JS' 5 Best forEach Tutorials
At Mastering JS, we typically recommend using
for/of
loops to iterate through an array in JavaScript. However, forEach()
is still very common, and it is sometimes more convenient for one-liners.
Here's some of our best tutorials for JavaScript
forEach()
:JavaScript arrays have a
forEach()
function, but general objects do not. This tutorial explains 3 ways to iterate through an object using forEach()
: using Object.keys()
, Object.values()
, and Object.entries()
.You can't use the
break
statement with forEach()
, because forEach()
is a function, not a loop. If you want to break out of a forEach()
loop, the easiest way is to use .every()
instead of .forEach()
. This tutorial presents 3 ways to simulate break
in a forEach()
.The
forEach()
function calls your callback with 3 parameters. Most forEach()
loops only use the first parameter, the value. The 2nd parameter is the current array index. This tutorial shows you how to get the array index.Because
forEach()
is a function, not a loop, you can't use continue
. However, with forEach()
, return
behaves like continue
. This tutorial presents 2 alternatives for simulating continue
with forEach()
.The
forEach()
function doesn't work well with async await. This is one of the major reasons why we recommend for/of
over forEach()
. This tutorial presents 2 alternative patterns that simulate async forEach()
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