3 Types of for Loops in JavaScript

zain ul abdin - Aug 21 - - Dev Community

We all know and love the classic for loop, but did you know that JavaScript has a few other powerful for loop options up its sleeve?

1) for/in: This one is very useful to iterate over the keys of an object and manipulating object properties.

Example:

const obj = {name: "JavaScript", type: "Language"};
for (let key in obj) {
    console.log(key); // outputs "name" and "type"
}
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2) for/of: This one is optimal when your focus is on the values rather than the keys or indices of iterable objects, such as arrays or strings.

Example:

const arr = ["JavaScript", "is", "versatile"];

for (let value of arr) {

  console.log(value);

}
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3) forEach: This one is a gem, as it offers convenience and readability, helping you iterate over arrays with minimal syntax, so you can focus on the logic within the loop rather than the iteration process itself.

Example:

const arr = ["JavaScript", "is", "versatile"];

arr.forEach(value => console.log(value));
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Which of these is your favorite?

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