Group
File Handling in C#
Objective
1. The program should accept the file name of the BMP image.
2. It will open the file in binary mode and check if the first two bytes are equal to 0x42 (B) and 0x4D (M).
3. If the bytes match, the program will print a message confirming that the file seems to be a valid BMP file.
4. If the bytes do not match, the program will inform the user that the file may not be a valid BMP image.
Create a C# program to check if a BMP image file seems to be correct. It must see if the first two bytes are B and M (ASCII codes 0x42 and 0x4D).
Example C# Exercise
Show C# Code
using System;
using System.IO;
class BMPValidator
{
// Main method: entry point of the program
static void Main(string[] args)
{
// Check if the user has provided a file name
if (args.Length == 1)
{
string fileName = args[0]; // The file name passed as an argument
// Call the method to validate the BMP file
bool isValidBMP = ValidateBMPFile(fileName);
// Display the result based on the validation
if (isValidBMP)
{
Console.WriteLine("The file is a valid BMP image.");
}
else
{
Console.WriteLine("The file is not a valid BMP image.");
}
}
else
{
Console.WriteLine("Please provide the file name of the BMP image.");
}
}
// Method to check if the file is a valid BMP file based on the first two bytes
static bool ValidateBMPFile(string fileName)
{
try
{
// Open the file in binary mode and read the first two bytes
using (FileStream fs = new FileStream(fileName, FileMode.Open, FileAccess.Read))
{
byte[] header = new byte[2];
fs.Read(header, 0, 2); // Read the first two bytes of the file
// Check if the first two bytes are 0x42 (B) and 0x4D (M)
if (header[0] == 0x42 && header[1] == 0x4D)
{
return true; // The file starts with "BM", so it is likely a BMP file
}
else
{
return false; // The file does not start with "BM", so it is not a BMP file
}
}
}
catch (Exception ex)
{
// Handle any exceptions that might occur (e.g., file not found, access errors)
Console.WriteLine($"Error: {ex.Message}");
return false;
}
}
}
Output
//When run with parameters:
bmpValidator image.bmp
The file is a valid BMP image.
//If the file doesn't match the BMP header:
bmpValidator nonImage.txt
The file is not a valid BMP image.