Code

How to handle asynchronous For loop in JavaScript

October 31, 2021
8 min
By
Prabhanu
Share

Since JavaScript is a single-threaded programming environment, some times it gives confusing outputs when time-consuming processes are executed middle of a code block. Using Asynchronous JavaScript such as async, await and promises developers can overcome the occurrence of those confusing outputs.

From today’s article, I am going to talk about how an asynchronous for loop can be handle in JavaScript.

Before moving further it would be better to have mentioned that I am not going to explain basic concepts of async, await and promises in JavaScript. I am going to explain only about handling asynchronous for loop.

Example time-consuming function

I have created a time-consuming function to show how it works with different for loops.

Is forEach() wait for results?

Test using an asynchronous function.

results:

“Async for loop without wait”

From this example, we can clearly see forEach(), not giving the expected results and not waiting until the finishing of execution of the time-consuming function.

Q: How to write For Loop to wait for results?

a: using thefor loop in an asynchronous function. 😀

let’s see an example of how to do it

result:

for loop gave the expected answer and waited until the finishing of execution of the time-consuming function.

Don’t hesitate to share any comment with me.

More news