JavaScript: Loops

JavaScript is unarguably one of the most popular programming languages in the world, and it offers many tools and features for web developers. One of these features is loops. Loops are crucial for controlling the flow of your programs and repeating tasks efficiently. In this article, we will explore JavaScript loops, analyzing their types, use cases, and best practices. By the end of this article, you will have the basic knowledge and skills to master loops and improve your JavaScript coding skills.

1. Understanding loops

   • What are loops?

   • Why do we need loops?

2. The Three Essential Loop Types

   • 'for' loops

   • 'while' loops

   • 'do....while' loops

3. Loop Use Cases

   • Repeating Task

   • Looping Through Object Properties

   • Iterating Over Data

4. Conclusion

Understanding Loop

What are loops?

Loops essentially means the quick and easy way of doing something repeatedly, without any need to go through the process of resetting it one after the other. You can think of loops as the alarm on your mobile phone, when you set up the alarm, for a certain day and time, maybe from Monday to Friday, as long as the days are between Monday and Friday the alarm will keep on repeating itself instead of setting the alarm each day, Loops save us from that stress. There are many types of loops, but all the loops do almost the same thing, which is repeating a certain task for a number of times. Below are the three major types of javascript loops.

1. 'for' Loops

2. 'While' Loops

3. 'do...while' Loops

Why do we need loops?

Basically, loops are used for writing a repetitive task in JavaScript without having to write the same line of code multiple times, with this, loops increase our code Readability and simplicity and minimize our line of code.

The Three Essential Loop Types

There are three essential loop types, which are for loop, while loop, and do...while loop. Although fundamentally all the loop type does the same thing, still there are some slight differences in their use cases.

1. For Loop

   for loop is the most common and the most concise way of writing the loop structure in JavaScript. A for loop is written based on three steps, which are the initialization, the Condition, and the Increment/Decrement. The three steps are shown in the chart below.

   

For loop is mainly used when we know the number of times we want the code to repeat itself, Here is the scenario, Assume you went to a coffee shop to use their internet, then the attendant told you that "for this internet to work you have to take nothing more than five cup of a coffee" which means if you take six cup of coffee the internet will not work. Immediately after the coffee passes five the network will stop working automatically, this is how the for loop work in JavaScript.

Below is the Syntax:

1. While loop

While loop is another means of writing repetitive code in javascript and using the same scenario we used in the for loop, it simply means when the coffee shop attendant says "While you're here take whatever you want" which means you can take as many coffees as you want so far you're still in that particular shop. This is exactly how JavaScript while loop works, While loop works When you don't know exactly how many times you need to loop, or when you need to loop until a certain condition is met. The while loop is just like repeating the if statement.

Syntax:

1. do...while loop

   The do...while loop is very similar to the while loop, The only difference is that the code block is always executed at least once, even if the condition is false.

   

• The do...while loop executes the statement first without checking the condition.

• After executing the statement it checks the condition and continues if the condition is true.

• It stops executing the statement if the condition is false.

• It should also be noted that whether the condition is true or false the statement is executed at least once.

Syntax:

Loops are essential in JavaScript for many reasons, below are some of the use cases:

• Repeating Task: Loops are used for repeating tasks in JavaScript instead of going through the stress of writing the same code over and over again. Below is an example of a code to print numbers 1-10 using the 'for' loop.

• Iterating Over Data: A loop also allows iteration that is going through a data one after the other to perform a specific task on each data, in the example below, for loops are used to go through each number and perform summation on them.

  

Conclusion

Loops are generally a line of code that is used for repeating a task over a specific condition, instead of writing the same line of code multiple times. There are mainly three types of JavaScript loops and they all perform the same purpose.