Comments

In C#, comments allow a developer to add explanatory or documenting notes to code. They do not affect program execution and are ignored by the compiler. C# has three types of comments:

Single-line comments

Single-line comments start with two characters: //. Everything after these characters until the end of the line is considered a comment.


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// This is a single-line comment
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Multi-line comments

Multi-line comments use the /* ... */ construct. They can span multiple lines.


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/*
This is a multi-line comment.
It can span multiple lines.
*/
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XML documentation

Comments of the form /// are used to create documentation directly in code. Such comments are usually applied to describe classes, methods, and their parameters. This is especially useful for auto-generating documentation.


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/// <summary>
/// This method calculates the sum of two numbers.
/// </summary>
/// <param name="a">The first number</param>
/// <param name="b">The second number</param>
/// <returns>The sum of numbers a and b</returns>
public int Add(int a, int b)
{
    return a + b;
Line 1, Char 1

Exercises

Run the code and look at the result. Then comment out the second line of code using a single-line comment, run the code again, and compare the results.


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Console.WriteLine("Faster");
Console.WriteLine("Higher");
Console.WriteLine("Stronger");
Line 1, Char 1

Using a multi-line comment, comment out the second and third lines. Run the code and compare the results.


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Console.WriteLine("Faster");
Console.WriteLine("Higher");
Console.WriteLine("Stronger");
Line 1, Char 1

Think about when it is more convenient to use single-line comments and when multi-line comments are better.