How many types of comments are in javascript?
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The JavaScript comments are meaningful way to deliver message. It is used to add information about the code, warnings or suggestions so that end user can easily interpret the code. The JavaScript comment is ignored by the JavaScript engine i.e. embedded in the browser. Advantages of JavaScript commentsThere are mainly two advantages of JavaScript comments.
Types of JavaScript CommentsThere are two types of comments in JavaScript.
JavaScript Single line CommentIt is represented by double forward slashes (//). It can be used before and after the statement. Let’s see the example of single-line comment i.e. added before the statement. Test it NowLet’s see the example of single-line comment i.e. added after the statement. Test it NowJavaScript Multi line CommentIt can be used to add single as well as multi line comments. So, it is more convenient. It is represented by forward slash with asterisk then asterisk with forward slash. For example: It can be used before, after and middle of the statement. Test it NowJavaScript comments can be used to explain JavaScript code, and to make it more readable. JavaScript comments can also be used to prevent execution, when testing alternative code. Single Line CommentsSingle line comments start with Any text between This example uses a single-line comment before each code line: Example // Change heading: // Change paragraph: Try it Yourself » This example uses a single line comment at the end of each line to explain the code: Example let x = 5; // Declare x, give
it the value of 5 Try it Yourself » Multi-line CommentsMulti-line comments start with Any text between This example uses a multi-line comment (a comment block) to explain the code: Example
/* Try it Yourself » It is most common to use single line comments. Using Comments to Prevent ExecutionUsing comments to prevent execution of code is suitable for code testing. Adding This example uses // to prevent execution of one of the code lines: Example //document.getElementById("myH").innerHTML = "My First Page"; Try it Yourself » This example uses a comment block to prevent execution of multiple lines: Example /* Try it Yourself » Programming languages offer an option of leaving notes for yourself or others. The JavaScript comment feature simplifies the production of more readable code. They are easy to write and recognize: a JavaScript comment block (also known as the multi-line comment) begins with */ , while a single line comment starts with //. In this quick tutorial, you'll learn how to write JavaScript comments and be able to leave notes in your JavaScript code. JavaScript is not
the only programming language to have the comment function in their syntax: HTML offers it as well. The JavaScript commenting out means that you take a part of the code and
surround it with JavaScript comment symbols. Comments are not executed by the browser, which means that they won't be displayed. Check out the example of commenting out a single-line below: Example
This example illustrates the commenting out a block of code: Example
Therefore, the JavaScript comment lets you comment a line, a part of it, or a block of code. This feature can be used for debugging your code to find the location of a bug quickly. Comment out a part of the code so you don't have to delete a part of it to see whether a bug is in that line. Pros
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Single-line comments are used to comment a part of a line or a full line of code in JavaScript. You can use it for either explaining the code or debugging (commenting out to prevent the execution by the browser). The example below uses a single-line comment to explain a line of code below the comment: Example
In the example below, a comment is written on the same line as the code itself: Example
For a single-line comment, you have to write two forward slashes: JavaScript multiline comment has the same purpose as a single-line comment. JavaScript comment
block starts with two symbols: You can use JavaScript multiline comment for leaving a long comment or commenting out larger parts of code while debugging: Example
How many types of comment are there?There are mainly two types of comments as follows: Line comment. Block comment.
What is comments in JS?JavaScript comments can be used to explain JavaScript code, and to make it more readable. JavaScript comments can also be used to prevent execution, when testing alternative code.
What is the right kind of JavaScript comment?In JavaScript, single-line comments begin with // . It will ignore all the things immediately after // syntax until the end of that line. This is also known as inline commenting when we use // syntax alongside codes lines.
Which symbol is used for comments in JavaScript?Example 1: This example illustrates the single line comment using //.
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