How Does a While Loop Start in Javascript

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A while loop in Javascript allows you to execute a block of code repeatedly as long as a specified condition is true. It’s called a “while” loop because it continues to loop “while” a certain condition is met.

Javascript while loop

You start writing while loop by stating the innitial value followed by the condition: The syntax for a while loop in JavaScript is:

let variable = innitialvalue;
while (condition) {
  // code block to be executed
}

The “condition” in the while loop can be any expression that evaluates to a boolean value, i.e. either true or false. The code block inside the while loop will be executed repeatedly until the condition evaluates to false.

It’s important to note that if the condition in the while loop never evaluates to false, the code block inside the loop will run indefinitely, causing an infinite loop. To avoid this, you must make sure that the condition will eventually evaluate to false.

A simple example of a while loop in action is:

let i = 0;
while (i < 5) {
  console.log(i);
  i++;
}

In this example, the code block inside the while loop will execute five times. The value of the variable “i” will be incremented by 1 each time the code block is executed. The first time the code block is executed, “i” will be 0. The second time, “i” will be 1, and so on, until “i” is equal to 5. At that point, the condition (i < 5) will evaluate to false, and the while loop will stop executing.

In conclusion, while loops are a valuable tool for front-end developers to have in their toolkit. They allow you to repeat a block of code as long as a specified condition is true. If you’re new to front-end development, make sure to understand the basics of while loops so that you can use them effectively in your code. Happy coding!

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Hi there! I am Avic Ndugu.

I have published 100+ blog posts on HTML, CSS, Javascript, React and other related topics. When I am not writing, I enjoy reading, hiking and listening to podcasts.