Are you new to programming in JavaScript? Do you want to know how to comment your code? In this article, we’ll show you how to comment in JavaScript.
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Introduction
In JavaScript, there are two ways to create comments: single-line and multi-line.
Single-line comments are created by using the double forward slash (//) at the beginning of a line. Anything on the same line after the double forward slash will be ignored by the JavaScript interpreter:
// This is a single-line comment.
Multi-line comments are created by using a forward slash and an asterisk (/*) at the beginning of a line, and an asterisk and a forward slash (*/) at the end of a line. Anything between the /* and */ will be ignored by the JavaScript interpreter:
/* This is a
multi-line comment. */
Basic Syntax
To write a single-line comment in JavaScript, you place two slashes “//” in front of the code or text you wish to haveTranslated into English, this would look like:
// This is a single-line comment in JavaScript.
Everything following the slashes will be ignored by the JavaScript interpreter. This means that you can place a comment on the same line as code:
x = x + 1; //this is how we increment x by 1.
You can also place comments before code on a separate line:
//this is how we increment x by 1.
x = x + 1; Or, you can comment out pieces of code that you don’t want executed without having to delete them from your program:
//x = x + 1; /* the preceding line is now a comment */
Multi-line Comments
Multi-line comments start with /* and end with */. Any text between /* and */ will be ignored by JavaScript.
Here is an example:
/*
This is a multi-line comment.
You can put anything you want here.
*/
Nested Comments
Nested comments are not allowed in JavaScript. That is, you cannot have a comment within another comment. This can cause problems if you’re trying to comment out a large section of code that includes other comments.
Inline Comments
JavaScript comments are annotations in the source code of a program that intend for a programmer to directly leave themselves or others with information about the code. The JavaScript comments can be single line as well as multiline.
// This is an inline comment in JavaScript
Multiline JavaScript comments are created by enclosing the text between /* and */.
/* This is a
multiline comment in JavaScript */
Inline JavaScript comments are created by precede the text with //
//This is an inline comment in JavaScript
Conclusion
Now that you know the basics of commenting in JavaScript, it’s time to put them into practice. Use comments liberally throughout your code to help make it more readable and understandable.
And, when working on collaborative projects, don’t forget to use coding conventions to standardize the way comments look. This will make it easier for everyone on the team to understand each other’s code.
