# C# program to convert a decimal number into an octal number

Here, we are going to learn how to convert a decimal number into an octal number in C#? By Nidhi Last updated : April 15, 2023

## Decimal to Octal Conversion in C#

Here we will read a decimal number and then convert it into a corresponding octal number.

## C# program for decimal to octal conversion

The source code to convert a decimal number to the octal number is given below. The given program is compiled and executed successfully on Microsoft Visual Studio.

```//C# program to convert a decimal number into an octal number.

using System;

class Program
{
static void Main(string[] args)
{
int decNum = 0;
int octNum = 0;
string temp = "";

Console.Write("Enter a Decimal Number :");

while (decNum != 0)
{
temp += decNum % 8;
decNum = decNum / 8;
}

for (int i = temp.Length - 1; i >= 0; i--)
{
octNum = octNum * 10 + temp[i] - 0x30;
}

Console.WriteLine("Octal Number is " + octNum);
}
}
```

## Output

```Enter a Decimal Number :11
Octal Number is 13
Press any key to continue . . .
```

## Explanation

In the above program, we create a class Program that contains the Main() method, In the Main() method we read a decimal number from user input and then convert the decimal number into the corresponding octal number.

```while (decNum != 0)
{
temp += decNum % 8;
decNum = decNum / 8;
}
```

In the above code, we find the remainder of the decimal number after dividing by 8 and then concatenate into the string, because the base of the octal number is 8.

```for (int i = temp.Length - 1; i >= 0; i--)
{
octNum = octNum * 10 + temp[i] - 0x30;
}
```

In the above code, we reversed the remainder string and covert into the integer number and then print the result on the console screen.