How can I get the position of an object during map function? [duplicate]

Question

When you use for function you can save the position of an object like (example):

for (var i = 0; i < array.length; i++) { var position = i; }

but I don't know how I can get the position an how I can know if it is the last using map function

array.map((object) => { })

Someone can help?

developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/… — tkausl
– tkausl, Commented Aug 23, 2019 at 13:03

Dupocas · Accepted Answer · 2020-03-15 11:41:59Z

7

The second parameter for the function provided to map is the current index of the element

arr.map((item, index) =>{ if(index === arr.length-1) console.log('last one') })

answered Aug 23, 2019 at 13:03

21.5k7 gold badges44 silver badges59 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

and it's possible to know which is the last?

Neel Rathod · Accepted Answer · 2019-08-23 13:04:53Z

In every of array methods (map(), forEach() etc..), the second parameter is an index of an array.

const array1 = [1, 2, 3]; array1.map((value, i) => { console.log(i); }); const array2 = [1, 2, 3]; array2.forEach((value, i) => { console.log(i); });

Jackkobec · Accepted Answer · 2019-08-23 13:03:59Z

1

array.map((object, index) => { var position = index; })

answered Aug 23, 2019 at 13:03

6,9871 gold badge42 silver badges39 bronze badges