BMP width & height, FileStream C# Exercise - C# Programming Course

// Import the necessary namespaces for file handling
using System;
using System.IO;

class BMPDimensions
{
    // Main method where the program starts
    static void Main(string[] args)
    {
        // Prompt the user to enter the path of the BMP file
        Console.WriteLine("Enter the path of the BMP file:");

        // Get the file path from user input
        string filePath = Console.ReadLine();

        // Check if the file exists
        if (File.Exists(filePath))
        {
            try
            {
                // Open the BMP file for reading in binary mode
                using (FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read))
                {
                    // Create a binary reader to read the BMP file data
                    using (BinaryReader reader = new BinaryReader(fs))
                    {
                        // Read the 'BM' file type (2 bytes) to confirm it's a BMP file
                        string fileType = new string(reader.ReadChars(2));
                        if (fileType != "BM")
                        {
                            Console.WriteLine("This is not a valid BMP file.");
                            return;
                        }

                        // Skip to the width and height data in the BMP header
                        reader.BaseStream.Seek(18, SeekOrigin.Begin);

                        // Read the width and height (4 bytes each)
                        int width = reader.ReadInt32();
                        int height = reader.ReadInt32();

                        // Display the width and height of the BMP image
                        Console.WriteLine("Width: " + width + " pixels");
                        Console.WriteLine("Height: " + height + " pixels");
                    }
                }
            }
            catch (Exception ex)  // Catch any errors that occur during reading
            {
                // Output an error message if an exception is thrown
                Console.WriteLine("An error occurred: " + ex.Message);
            }
        }
        else
        {
            // Inform the user if the specified file doesn't exist
            Console.WriteLine("The specified file does not exist.");
        }
    }
}