Faster array looping in React-Native

Question

Why cant I use this approach in React-Native for a faster looping:

var array = this.myinputfields.textfields.length;
for (let i = 0; i < array; i++)

I know this can be done in JavaScript but not in React-Native. Is there a way to loop faster through an array?

@BreakBB No errors, as I have mentioned I am just asking if there is another approach for a faster performance. — user11558118
– user11558118, Commented Jun 13, 2019 at 13:25
@BreakBB the one that I have posted doesnt work in React-Native, it throw error. — user11558118
– user11558118, Commented Jun 13, 2019 at 13:26
@R3tep it seems like I was wrong, it actually works. I tried it some days ago but it didnt, maybe there was another problem. However, what's your opinion, do you think this is a faster approach? — user11558118
– user11558118, Commented Jun 13, 2019 at 13:32

R3tep · Accepted Answer · 2019-06-13 13:30:40Z

1

You can use this faster way

for (let l = this.myinputfields.textfields.length; l--;) {}

But you loop on the array in reverse

answered Jun 13, 2019 at 13:30

R3tep

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4 Comments

can you explain why this is a faster way?

If you read the line, you can see there is one variable less and one operation less. There is only one incrementation and no comparison with <

When should I use this and when the other approach?

You can use this way if it's possible to loop on the array in reverse mode. The other one if it's not possible.