Published Jan 9, 2023
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A comment is a piece of text within a program that is not executed. It can be used to provide additional information to aid in understanding the code.

Single-line Comments

For single-line comments, the compiler ignores any text after two consecutive forward slashes (//) on the same line.

// Comment goes here
executing code // Comment goes here

Multi-line Comments

Multi-line comments begin with /* and end with */. The compiler ignores any text in between.

This is all commented out.
None of it is going to run!


The following examples show various comment styles:

// This line will denote a comment in C-sharp.
Console.WriteLine("Hello World!"); // This is a comment.
This is a multi-line

XML Comments

XML comments are structured comments that produce API documentation. The C# compiler produces an XML file that contains structured data representing the comments. Other tools can process that XML output to create human-readable documentation in the form of web pages or PDF files, for example.


The following is a single-line XML comment, which uses three forward slashes (///):

/// XML Comment goes here

Multi-line XML comments are similar to regular multi-line comments, except that an extra asterisk * is used in the opening:

XML Comments go here


XML tags embedded in XML comments are used to signal a specific functionality of the XML comment to the compiler. The <summary> tag in the following example describes a type or a member, in this case, the public class MyClass:

/// <summary>
/// This class performs an important function.
/// </summary>
public class MyClass {}

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