Access to ES6 array element index inside for-of loop

Question

We can access array elements using a for-of loop:

for (const j of [1, 2, 3, 4, 5]) {   console.log(j); } 

How can I modify this code to access the current index too? I want to achieve this using for-of syntax, neither forEach nor for-in.

Answer 1

Use Array.prototype.keys:

for (const index of [1, 2, 3, 4, 5].keys()) {    console.log(index);  }

If you want to access both the key and the value, you can use Array.prototype.entries() with destructuring:

for (const [index, value] of [1, 2, 3, 4, 5].entries()) {    console.log(index, value);  }