How to get an array of strings based on Uint8Array values (map Uint8 values to String/s)

Question

new Uint8Array([1,2,3]).map((v,y)=>"0"+v+"0"+y)
> Uint8Array(3) [ 100, 201, 46 ] // actual
> ["0100","0201","0302"] // expected
new Uint8Array([1,2,3]).map((v,y)=>v+1)
> Uint8Array(3) [ 2, 3, 4 ] // actual as expected
[1, 2, 3].map(x => "0"+x);
> Array ["01", "02", "03"] // actual as expected

Since 302 is bigger than 256 (Uint8 max size), when converted we get 302%256 which is 46. Put this in as a proof we don't get just any number type, but specifically Uint8.

So how do I get an array of strings based on Uint8Array values?

Answer 1

the problem here is that Uint8Array.map returns an Uint8Array object you need to convert it in a normal array in order to achieve the result you are looking for

const uint8Array = new Uint8Array([1,2,3])
const res1 = uint8Array.map((v,y)=>"0"+v+"0"+y)
const res2 = [...uint8Array].map((v,y)=>"0"+v+"0"+y)
console.log(res1, res2)

• BogdanBiv: this is so much simpler than I was thinking of a solution -- with custom for loops / custom map function