Introduction:

Understanding how to convert decimal numbers to hexadecimal is crucial for working with low-level programming, memory addresses, and cryptography. In this blog, we will examine into various methods for converting decimal to hexadecimal in C#, providing detailed explanations and examples to enhance your understanding.

Method 1: Using Built-in Function - Decimal.ToString("X")

The easiest way to convert a decimal number to hexadecimal in C# is by using the built-in function ToString() with the "X" format specifier. The "X" format specifier indicates hexadecimal format. Here's a simple C# program demonstrating this method:

using System;

class Program
{
    static void Main()
    {
        int decimalNumber = 255;
        string hexadecimalNumber = decimalNumber.ToString("X");
        Console.WriteLine($"Decimal: {decimalNumber}, Hexadecimal: {hexadecimalNumber}");
    }
}

Output:

Decimal: 255, Hexadecimal: FF

In this method, we use the ToString("X") function to convert the decimal number 255 to its hexadecimal representation, which is "FF". The "X" format specifier ensures that the resulting string contains the hexadecimal representation of the number.

Method 2: Using a Custom Function

If you want to convert decimal to hexadecimal without relying on the built-in function, you can implement a custom function. One way is to repeatedly divide the decimal number by 16 and record the remainders to build the hexadecimal representation. Here's an example of a custom function in C#:

using System;

class Program
{
    static string DecimalToHexadecimal(int decimalNumber)
    {
        string hex = "";
        while (decimalNumber > 0)
        {
            int remainder = decimalNumber % 16;
            char hexDigit = (char)(remainder < 10 ? remainder + '0' : remainder + 'A' - 10);
            hex = hexDigit + hex;
            decimalNumber /= 16;
        }
        return hex;
    }

    static void Main()
    {
        int decimalNumber = 255;
        string hexadecimalNumber = DecimalToHexadecimal(decimalNumber);
        Console.WriteLine($"Decimal: {decimalNumber}, Hexadecimal: {hexadecimalNumber}");
    }
}

Output:

Decimal: 255, Hexadecimal: FF

In this custom function, we divide the decimal number by 16 in each iteration and obtain the remainder. If the remainder is less than 10, we add it to the result as a character representing the digit. Otherwise, we convert the remainder to its hexadecimal representation (A-F) using ASCII values and add it to the result.

Conclusion:

This blog explored various methods to convert decimal numbers to hexadecimal in C#. We started with the simplest method, using the built-in ToString("X") function, which is convenient and efficient for most use cases. We then demonstrated a custom function that provides insight into the underlying process of conversion, helpful for learning and understanding the concepts better.