ForOf.md

For Of

• The for-in loop is for looping over object properties.
• The for-of loop is for looping over the values in an array.
• for-of is not just for arrays, it also works on most array-like objects.

Syntax	Description
for-in	Object Not recommend to use for array because index is generated as 'string'.
for-of	Array, Array-like object

for-in

Q1

let obj = {a:1, b:2};

for (let prop in obj){
  console.log(prop);
}

Q1-Answer

a
b

---

Q2

NOT recommend to use for-in in Array because index is 'string'.

let array = [10, 20, 30];

for (let index in array){
  console.log(index);
  console.log(typeof index); 
}

Q2-Answer

0
string
1
string
2
string

for-of

Q3

let array = [10, 20, 30];
for (let value of array){
  console.log(value);
}

Q3-Answer

10
20
30