Decimal to Octal Conversion in C#

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Decimal to Octal Conversion in C# with Examples

In this article, I am going to discuss Decimal Number to Octal Number Conversion in C# with Examples. Please read our previous article, where we discussed Binary to Octal Number Conversion in C#. At the end of this article, you will understand how to convert a decimal number to an octal number in C#.

Decimal Number System in Computer:

Decimal is a term that describes the base-10 number system. The decimal number system consists of ten single-digit numbers: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. Example: (35)₁₀

Octal Number System in Computer:

The octal numeral system or oct describes the base-8 number system and uses the digits 0 to 7. Octal numerals can be made from binary numerals by grouping consecutive binary digits into groups of three (starting from the right). Example: (5303)₈

Decimal to octal conversion example:

Decimal number ((127)₁₀ 

1. Divide 127 by 8. 127 ÷ 8= 15(Quotient) and (7) Remainder
2. Divide 15 by 8 again. 15 ÷ 8 = 1(Quotient) and (7) Remainder
3. Divide 1 by 8, we get. 1 ÷ 8 = 0(Quotient) and (1) Remainder

The quotient is 0 now, no more division can be possible. So, by taking the remainders in reverse order, we get the octal number. Hence, (127)₁₀ = (177)_8. For better understanding, please have a look at the below image.

Logic to Convert Decimal to Octal in C# 

To find the conversion of Decimal to Octal number simply need to follow the below steps:

1. First, we divide the decimal numbers by 8.
2. Then we get quotient and remainder.
3. If the remainder is greater than 0 then again, we repeat step 1 and step 2.
4. Then we store the number from bottom to top and we get the octal number

Example: Decimal to Octal Conversion in C# 

The following C# Program will convert a decimal number to its equivalent octal number.

using System;
class Demo
{
    public static void Main()
    {
        int decValue, counter, i = 1, j;
        int[] octalValue = new int[80];
        decValue = 127;
        counter = decValue;
        Console.WriteLine("Decimal Number:{0}", decValue);
        while (counter != 0)
        {
            octalValue[i++] = counter % 8;
            counter /= 8;
        }

        Console.Write("Octal Number: ");
        for (j = i - 1; j > 0; j--)
            Console.Write(octalValue[j]);
        Console.Read();
    }
}

Output:

Example: Taking input from the user

In the following C# program, we will take the decimal number from the user and then convert the decimal number to its equivalent octal number and print it on the console.

using System;
public class DecimaltoOctal
{
    public static void Main()
    {
        int i, j, Octal = 0, dn;
        Console.Write("Enter the Decimal Number : ");
        int DecimalNumber = Convert.ToInt32(Console.ReadLine());
        dn = DecimalNumber;
        i = 1;

        for (j = DecimalNumber; j > 0; j = j / 8)
        {
            Octal = Octal + (j % 8) * i;
            i *= 10;
            DecimalNumber /= 8;
        }

        Console.WriteLine("The Octal Number is {1}.\n\n", dn, Octal);
        Console.ReadKey();
    }
}

Output:

C# Code (Using function)

In the below example, we have created one method to convert the decimal number to an octal number.

using System;
class Decimaltooctal
{
    static void DecToOctal(int n)
    {
        int[] octalNum = new int[100];
        int i = 0;
        while (n != 0)
        {
            octalNum[i] = n % 8;
            n /= 8;
            i++;
        }
        Console.Write("Octal Number : ");
        for (int j = i - 1; j >= 0; j--)
            Console.Write(octalNum[j]);
    }
    public static void Main()
    {
        Console.Write("Enter the Decimal Number : ");
        int DecimalNumber = Convert.ToInt32(Console.ReadLine());
        DecToOctal(DecimalNumber);
        Console.ReadKey();
    }
}

Output:

In the next article, I am going to discuss Hexadecimal to Octal Conversion in C# with Examples. Here, in this article, I try to explain how to convert a decimal number to an octal number in C# with Examples and I hope you enjoy this Decimal to Octal Conversion in C# article.

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About the Author: Pranaya Rout

Pranaya Rout has published more than 3,000 articles in his 11-year career. Pranaya Rout has very good experience with Microsoft Technologies, Including C#, VB, ASP.NET MVC, ASP.NET Web API, EF, EF Core, ADO.NET, LINQ, SQL Server, MYSQL, Oracle, ASP.NET Core, Cloud Computing, Microservices, Design Patterns and still learning new technologies.