In most cases they can be used as alternatives as they all repeatedly execute the given code, but there are various situations in one is prefered over the others. Tech Marble.js – new open source framework for JavaScript Other JavaScript loopsįor loops are not the only type provided in JavaScript, so I’d like to present a number of other loops very briefly. They differ because the for…in loop iterates over all enumerable properties, which also includes those added to the array’s prototype. Let’s take a look at an example:įor the for…of, however it will not have the last element:

The regular for loop would log the array’s elements just the same as for…of does.Īnother difference is when we add additional properties to an array’s prototype and then we’re trying to loop over an array. The reason why it’s being logged in such way is because for…in logs only properties with a value, while for…of logs every element from the array. The for…of loop however, will show a slightly different result: The first loop will only return one value: There is one more significant difference between these two, as shown in the below example.Īs we already know, both loops should log all the elements from the array, but is it really the same? As usual in such cases - the answer is no… Top 10 React Libraries Every JavaScript Professional Should Knowīefore we dive into newer solutions, let’s examine the for loop statement, which has been with us for quite some time now.Ĭonst scrumTeam = įor (let i = 0 i See other, JavaScript dedicated articles:

If you need to execute a few lines of code five times or display a component several times, this is exactly what you’re looking for! The main aim of using loops is to do something repeatedly.

For of loop javascript