Basics
Node.js Loops
Loop Structures
Node.js loops include for and while with async loop patterns.
Introduction to Loops in Node.js
Loops are fundamental constructs in programming that allow you to execute a block of code repeatedly. In Node.js, you can use loops such as for loops, while loops, and handle asynchronous operations within loops.
The For Loop
The for loop is used when you know in advance how many times you want to execute a statement or a block of statements. It consists of three parts: initialization, condition, and iteration.
Here is a basic example of a for loop in Node.js:
The While Loop
The while loop executes a block of code as long as a specified condition is true. Unlike the for loop, the while loop is more suited when the number of iterations is not known beforehand.
Below is an example of a while loop:
Asynchronous Loop Patterns
Handling asynchronous operations within loops can be tricky because traditional loops like for and while do not wait for asynchronous tasks to complete before proceeding to the next iteration. To handle asynchronous operations, you can use async/await or Promise.all.
Here is an example using async/await within a loop:
In this example, the delay function returns a promise that resolves after a given number of milliseconds. The asyncLoop function uses await to pause execution until the promise is resolved, ensuring that each iteration waits for the previous one to complete.
Conclusion
Node.js provides powerful constructs for handling loops, both synchronous and asynchronous. Understanding how to effectively use for and while loops, along with async patterns, is essential for writing efficient Node.js applications.
