Comments in C#
A comment is just a text that you can write to explain or describe your code.
There are two ways we can write cmments in C# - Multi line comments and single line comments
The multi-line comments begin with the characters "/*" and end with the characters "*/" as following:
/* this code calculates the
* area of a rectangle */
using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace ConsoleApplication1 { class Program { static void Main(string[] args) { int length; int breadth; int area; length = 20; breadth = 10; area = length * breadth; /* this code calculates the area of a rectangle */ Console.WriteLine("Length of Rectangle is : {0}", length); Console.WriteLine("Breadth of Rectangle is : {0}", breadth); Console.WriteLine("Area of Rectangle is : {0}", area); Console.ReadLine(); } } } |
Length of Rectangle is 20 Breadth of Rectangle is 10 Area of rectangle is 200 |
Commenting is often used as debugging aid. We can comment out a section of code to see what result it gives. For example take a look at the code ...
using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace ConsoleApplication1 { class Program { static void Main(string[] args) { int length; int breadth; int area; length = 20; breadth = 10; area = length * breadth; /* this code calculates the area of a rectangle Console.WriteLine("Length of Rectangle is : {0}", length); Console.WriteLine("Breadth of Rectangle is : {0}", breadth); */ Console.WriteLine("Area of Rectangle is : {0}", area); Console.ReadLine(); } } } |
We have commented out a section of code displaying the length and breadth of the rectangle. This gives the following output.
Area of rectangle is 200 |
The single-line comments begin with the characters "//" and you can write your comments only at this line as the following: // This is a single line comment If you want to write more than one line in your comment then you must begin each line with "//" characters as following: // This code is very complex to undestand // Refer to documentation at www.referencedesigner.com for details
using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace ConsoleApplication1 { class Program { static void Main(string[] args) { int length; int breadth; int area; length = 20; breadth = 10; area = length * breadth;// Calculate the area of rectangle Console.WriteLine("Area of Rectangle is : {0}", area); Console.ReadLine(); // The program ends here. // Now save it and hit F5 to run the program } } } |
This completes your understanding of the comments in C#. In the next chapter we will show you how to display the values of variables and string using the Writeline command. These comment and Writeline form the two building blocks of C# that you will use to experiment various example codes of C#