forEach loop through two arrays at the same time in javascript
47,810
Use the second parameter forEach
accepts instead, which will be the current index you're iterating over:
n = [1,2,3,5,7,8,9,11,12,13,14,16,17,18,20,21,22];
n.forEach((element, index) => {
console.log(element, index);
});
If you have two separate arrays to begin with, in each iteration, access the [index]
property of the other array:
var n = [1, 2, 3, 5, 7, 8, 9, 11, 12, 13, 14, 16, 17, 18, 20, 21, 22];
var m = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16];
n.forEach((num1, index) => {
const num2 = m[index];
console.log(num1, num2);
});
Author by
FilipeTeixeira
Architect, Neurobiologist and now adventuring through the oceans of data analysis. Started with R and I can't let it go.
Updated on September 12, 2020Comments
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FilipeTeixeira over 3 years
I want to build a
for
loop that iterates through two variables at the same time.n
is an array andj
goes from 0 to 16.var n = [1,2,3,5,7,8,9,11,12,13,14,16,17,18,20,21,22]; var m = [0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]; m.forEach(k => { n.forEach(i => { console.log(i, k) }); };
The final result should output:
1,0 2,1 3,2 5,3 (...)
Unfortunately this loop doesn't do that for some reason as it repeats every number 17 times.
What am I missing here?