using System;
using System.IO;
public class GifFile
{
public static void Main()
{
byte[] data = new byte[5];
BinaryReader file = new BinaryReader(File.Open("test.gif", FileMode.Open));
for (int i = 0; i < 5; i++)
data[i] = file.ReadByte();
file.Close();
if (data[0] == Convert.ToByte('G') &&
data[1] == Convert.ToByte('I') &&
data[2] == Convert.ToByte('F') &&
data[3] == Convert.ToByte('8'))
Console.WriteLine("Its a GIF8" + data[4]);
else
Console.WriteLine("It not gif file");
}
}