#javascript over array

Every programmer faces a "looping-in" over the countable data set. This data set can be maps, lists, arrays, or any other objects. There are a bunch of tools available to eliminate the exact problem. There are different arrays for different devices in the JavaScript language. So, here are the helpful procedures and methods applied to looping over arrays.

In this article, we will see all the lopping methods of JavaScript.

‘’for’’ loop

‘’for-in’’ loop

‘’.forEach()’’

‘’for-of’’ loop

"for" loop

This loop is quite old from ES1. It is used when the index and values of the array to be logged. For an example, const arr = ['a', 'b', 'c'] and index value is 0. The output will be like below.

"for-in" loop

It's the same old loop as a "for" loop, and it's old from ES1. For-in loop only visits keys, not values. But it is a bad option to skip arrays. It calls all assets keys countlessly, not only array objects. Never use "for-in" Because iteration is not guaranteed, the arrays will not be accessed in numeric order.

.forEach() the array method ES5

For looping arrays, "for" or "for-in" cannot be used, so ES5 method was introduced: Array.prototype.forEach(). It is a very simple method to get an array and elements easily. Please do not use this method because it does not work synchronously. Also, you cannot use it with "async, await." You can not "break.forEach()" loop everywhere. You can use "break" in "for" loops.

"for-of" ES6

"for-of" introduced in ES6. It works very well for looping arrays. You can use "await" in it, and also, it's easy to merge to "for-await-of." For outer scope, you can use "break" and continue."

Conclusion