1. The Standard For loop
let numbers = [10,20,30];
for(i = 0; i < a.length; i++ ){
console.log(numbers[i]);
}
π We can use break
, continue
, and return
inside of the standard for
loop.
2. forEach Loop
let numbers = [1,2,3];
numbers.forEach(function(value){
console.log(value);
}
- Now, we'll get exactly as the same output as in case of the standard for-loop.
π We CANNOT use break
or continue
inside forEach loop.
π We can use the return
keyword (forEach is anyway a function so it doesn't make any difference to use it)
3. For-in Loop
π It is used for looping over object properties.
- What happens if we loop through an array?
// Looping through Objects
let obj = {a:10, b:20, c:30};
for(let prop in obj){
console.log(prop) //0
console.log(typeof(prop)) //string
}
//Looping through an array
let numbers = [10,20,30];
for(let index in numbers){
console.log(index) //0
console.log(typeof(index)) // stringβ
}
4. For-Of Loop
π Use for-of to loop over itterables like arrays.
let numbers = [10,20,30];
for(let index of numbers){
console.log(index) //0
console.log(typeof(index)) // numberβ
}
Summary
- π The main difference between
for
andforEach
is the use ofbreak
,continue
, andreturn
- π The main difference between
for-in
andfor-of
is the former is used to iterate over Object properties and the latter is for iterables like arrays.
Top comments (2)
Thanks for the summary of the "for" loops.
Thank you for reading :)