Dotnet Library: C# Console Application Examples

1.C# PROGRAM TO ADD TWO NUMBERS / INTEGERS :

using System;

namespace CsharpPrograms

{

class Program

{

static void Main(string[] args)

{

int x;

int y;

int result;

Console.Write("\n Enter the first number to be added: ");

x=Convert.ToInt32(Console.ReadLine());

Console.Write("\n Enter the second number to be added: ");

y = Convert.ToInt32(Console.ReadLine());

result = x + y;

Console.Write("\n The sum of two numbers is: "+result);

Console.ReadLine();

}

2. C# PROGRAM TO ADD TWO NUMBERS / INTEGERS USING METHOD

using System;

namespace AddTwoNumsUsingFunc

    class Program

        static void Main(string[] args)

            int x, y, result = 0;

Console.WriteLine(">>>C# PROGRAM TO ADD TWO NUMBERS WITHOUT USING THIRD VARIABLE <<< ");

         Console.Write("\n Enter the first number to be added: ");

x = Convert.ToInt32(Console.ReadLine());// taking x value from keyboard

            Console.Write("\n Enter the second number to be added: ");

   y = Convert.ToInt32(Console.ReadLine()); // taking y value from keyboard

            result = Sum(x, y);     //calling function

            Console.WriteLine("\n The sum of two numbers is: {0} ", result);    /*printing the sum.*/

            Console.ReadLine();

        static public int Sum(int a, int b)

            int result = a + b;

            return result;

3. C# Program To Add Two Numbers/Integers without using Third Variable :

using System;

 

namespace CsharpPrograms

{

    class Program

    {

        static void Main(string[] args)

        {

 

            int x,y;

        Console.WriteLine(">>> PROGRAM TO ADD TWO NUMBERS WITHOUT USING THIRD VARIABLE <<< ");

            Console.Write("\n Enter the first number to be added: ");

            x=Convert.ToInt32(Console.ReadLine());         // taking x value from keyboard

            Console.Write("\n Enter the second number to be added: ");

            y = Convert.ToInt32(Console.ReadLine());         // taking y value from keyboard

            x = x + y;     /*assining the value of sum of x and y to x*/

 

          Console.WriteLine("\n The sum of two numbers is: "+x);    /*printing the sum.*/

          Console.ReadLine();

        }

    }

}

4. C# PROGARM TO GET PRODUCT OF TWO NUMBERS

using System;

namespace ProductOfTwoNumbers
{
    class Program
    {
        static void Main(string[] args)
        {

            int x, y;
            int result;
            Console.Write("\n Enter the first number : ");
x = Convert.ToInt32(Console.ReadLine()); /* reading 1st number from user*/
            Console.Write("\n Enter the second number: ");
y = Convert.ToInt32(Console.ReadLine()); /* reading 2nd number from user*/
            result = x * y;    /* storing the product in result*/
     Console.WriteLine("\n The product of two numbers is: {0} \n", result);
            Console.ReadLine();

        }
    }
}

5. C# program to print sum of series 1+2+3+....+n

using System;



namespace SumOfSeries

{

    class Program

    {

        static void Main(string[] args)

        {

            int sum = 0, i, n;

            Console.WriteLine("\n>>> C# Program to print Sum of Series 1+2+3+..+n <<<\n");

            Console.Write("\n Enter the number of terms:");

            n=Convert.ToInt32(Console.ReadLine());

            for (i = 1; i <= n; i++)

            {

                sum += i;

            }

            Console.WriteLine("\n Sum of series upto  {0} is : {1}", n, sum);

            Console.ReadLine();



        }

    }

}

6 . C# program to find reverse of a given number

using System;



namespace ReverseNumber

{

    class Program

    {

        static void Main(string[] args)

        {



            int num, rem, sum = 0, rev;

            Console.WriteLine("\n /** To Find Reverse Of a Number **/");

            Console.Write("\n Enter a number: ");

            num=Convert.ToInt32(Console.ReadLine());

            while (Convert.ToBoolean(num))

            {

                rem = num % 10;  //for getting remainder by dividing with 10

                num = num / 10; //for getting quotient by dividing with 10

                sum = sum * 10 + rem;

            }

            rev = sum;

            Console.WriteLine("\n The Reversed Number is: {0} \n\n", rev);

            Console.ReadLine();

        }

    }

}

7. C# Program to find whether the Number is Palindrome or not

using System;

namespace NumberPalindrome
{
    class Program
    {
        static void Main(string[] args)
        {
            int num, rem, sum = 0, temp;
            //clrscr();
            Console.WriteLine("\n >>>> To Find a Number is Palindrome or not <<<< ");
            Console.Write("\n Enter a number: ");
            num = Convert.ToInt32(Console.ReadLine());
            temp = num;
            while (Convert.ToBoolean(num))
            {
                rem = num % 10; //for getting remainder by dividing with 10
                num = num / 10; //for getting quotient by dividing with 10
                sum = sum * 10 + rem; /*multiplying the sum with 10 and adding
                           remainder*/
            }
            Console.WriteLine("\n The Reversed Number is: {0} \n", sum);
            if (temp == sum) //checking whether the reversed number is equal to entered number
            {
                Console.WriteLine("\n Number is Palindrome \n\n");
            }
            else
            {
                Console.WriteLine("\n Number is not a palindrome \n\n");
            }
            Console.ReadLine();
        }
    }
}

8. C# Program to Find Factorial of Number

using System;

namespace FactorialOfNumber

    class Program

        static void Main(string[] args)

            int num, i, fact = 1;

            //clrscr();

            Console.WriteLine("\n >>C# PROGRAM TO FIND FACTORIAL OF GIVEN NUMBER <<\n");

            Console.Write("\n Enter the Number whose Factorial you want: ");

            num=Convert.ToInt32(Console.ReadLine());

            for (i = num; i >= 2; i--) //i is intializing with num value and  is decremented till 2

                fact = fact * i; //fact is updating with changing value of i

            Console.WriteLine("\n The factorial of {0} is {1}.\n\n", num, fact);

            Console.ReadLine();

9. C# PROGRAM TO PRINT SMILING FACE / ASCII VALUE OF 1 :

using System;

namespace SmilingFace

    class Program

        static void Main(string[] args)

            int a = 1, i;

            for (i = 0; i < 250; i++) //prints love symbol 250 times

                Console.Write((char)a);

                //Console.Write((char)1);

            Console.ReadKey();

10.Implementing Addition of Two Matrices Using 2D-Arrays:

using System;

namespace MatrixAdditionProgram
{
    class Program
    {
        static void Main(string[] args)
        {
            //using 2D-ARRAYS
            int RowSize = 5, ColSize = 5;
            int[,] Matrix1 = new int[RowSize, ColSize];
            int[,] Matrix2 = new int[RowSize, ColSize];
            int[,] ResultMatrix = new int[RowSize, ColSize];
            int i, j;

            try
            {
                Console.WriteLine("\n >>> PROGRAM To PRINT ADDITION OF TWO MATRICES <<<");
                Console.Write("\n Enter the Size of a Matrix N*N (For Example:3*3) : ");
                string s = Console.ReadLine();
                string[] values = s.Split('*');
                RowSize = int.Parse(values[0]);
                ColSize = int.Parse(values[1]);

                if (RowSize > 5 || ColSize > 5)   //limiting the size of matrix
                {
                    Console.BackgroundColor = ConsoleColor.DarkRed; //changing background color to red
                    Console.WriteLine(" The Size Of Matrix should Be in Less Than 5 (limiting size of array)");
                    System.Console.ResetColor(); ///resetting color
                    Console.WriteLine("\n\n\t Press Enter key to exit....");
                    Console.ReadKey(); return;
                }

                else
                {

                    //Initializing all the elements to zero
                    for (i = 0; i < RowSize; i++)
                    {
                        for (j = 0; j < ColSize; j++)
                        {
                            Matrix1[i, j] = 0;
                            Matrix2[i, j] = 0;
                        }
                    }
                    //Reading elements of Matrix1
                    Console.WriteLine("\n Enter the elements of Matrix1({0}*{1})", RowSize, ColSize);
                    for (i = 0; i < RowSize; i++)
                    {
                        for (j = 0; j < ColSize; j++)
                        {
                            Console.Write(" Matrix1[{0},{1}] : ", i, j);
                            Matrix1[i, j] = Convert.ToInt32(Console.ReadLine());
                        }
                    }
                    //Reading elements of Matrix2
                    Console.WriteLine("\n Enter the elements of Matrix2({0}*{1})", RowSize, ColSize);
                    for (i = 0; i < RowSize; i++)
                    {
                        for (j = 0; j < ColSize; j++)
                        {
                            Console.Write(" Matrix2[{0},{1}] : ", i, j);
                            Matrix2[i, j] = Convert.ToInt32(Console.ReadLine());
                        }
                    }

                    //calculating ResultMatrix, by adding Matrix1 and Matrix2
                    for (i = 0; i < RowSize; i++)
                    {
                        for (j = 0; j < ColSize; j++)
                        {
                            ResultMatrix[i, j] = Matrix1[i, j] + Matrix2[i, j];
                        }
                    }

                    //Printing Result Matrix
                    Console.Write("\n\n\t*** Result Matrix ***\n\n\t");
                    for (i = 0; i < RowSize; i++)
                    {

                        for (j = 0; j < ColSize; j++)
                        {
                            if (ResultMatrix[i, j] < 10)
                            {
                                Console.Write(" 0" + Convert.ToString(ResultMatrix[i, j])); //Making number as 01,02,etc,.
                            }
                            else
                            {
                                Console.Write(" " + Convert.ToString(ResultMatrix[i, j]));
                            }

                            if (j == ColSize - 1) { Console.Write("\n\t"); }

                        }
                    }
                }
            }
            catch //to catch exceptions,suppose string entered as aRowSize or Colsize of matrix
            {
                Console.BackgroundColor = ConsoleColor.DarkRed;
                Console.WriteLine("WARNING:only Number are allowed, Enter Correct Input");
                Console.ResetColor();
            }

            Console.WriteLine("\n\n\t Press Enter key to exit....");
            Console.ReadLine();
        }
    }
}

10. C# PROGRAM TO GET ALL FILE PATHS IN A GIVEN DIRECTORY

11. C# PROGRAM TO GET FILE NAMES IN THE GIVEN DIRECTORY

using System;
using System.IO;

namespace GetFileNames
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                string FolderPath ;
                string[] Files;
                Console.WriteLine(" Enter the Directory Path to get File Names in it : ");
                FolderPath=Console.ReadLine();
                Files = Directory.GetFiles(FolderPath);
                Console.WriteLine("\n The FileNames with extension in given Directory are : \n\n");

                foreach (string FileName in Files)
                {
                    // Create the FileInfo object only when needed to ensure
                    // the information is as current as possible.
                    System.IO.FileInfo fi = null;
                    try
                    {
                        fi = new System.IO.FileInfo(FileName);
                    }
                    catch (System.IO.FileNotFoundException ex)
                    {
                        // To inform the user and continue is
                        // sufficient for this demonstration.
                        // Your application may require different behavior.
                        Console.WriteLine(ex.Message);
                        continue;
                    }
                    Console.WriteLine("{0}", fi.Name);
                   // Console.WriteLine("{0}", fi.Directory); //prints filepath
                   // Console.WriteLine("{0}", fi.DirectoryName); // prints directorypath
                }
                Console.ReadLine();
            }
            catch (DirectoryNotFoundException ex)
            {
                Console.BackgroundColor = ConsoleColor.Red;
                Console.WriteLine("\n\n Directory Not Found..Press any key to exit...");
                Console.ReadKey();
            }
        }

    }
}

12.Declaring constants in C#.NET

In this article we will see a small example of using constants in c#. constants are declared with a keyword const .
The program below is to find the area and perimeter of circle in which we use const .
In the program below we have declared PI as a constant which value is given as 3.14
It means PI value cannot be changed either at compile time or run-time .
Any Integral or string variables can be declared as constants.
We can also declare constants as public to use it in all the classes in a program.

using System;

namespace Constants

{

class Program

{

static void Main(string[] args)

{

//declaring const variable PI

const double PI = 3.14;

Console.WriteLine("*** www.ProgrammingPosts.blogspot.com ***");

Console.WriteLine(">>> c# Program to find Area and Perimeter of Circle <<< \n");

Console.Write("Enter radius value: ");

int r = Convert.ToInt32(Console.ReadLine()); //taking radius as input

double area = PI * r * r; //getting area of circle

Console.WriteLine("Are of circle is: " + area);

//if we try to assign a value to PI , we get compile-time error

//PI = 123;

double perimeter = 2 * PI * r; //getting perimeter of circle

Console.WriteLine("Perimeter of circle: " + perimeter);

Console.Read();

}

Dotnet Library

Friday, 15 November 2013

C# Console Application Examples