So im using a binaryreader to try and search a file for an array of bytes like so:

Code: [Select] void MapSearcher()
{
byte[] SearchBytes = new byte[] { 0x00, 0x00, 0x00, 0x70, 0x72, 0x6F, 0x6A };
long SearchPosition = 0x00;

BinaryReader br = new BinaryReader(File.OpenRead(MapFile));
br.BaseStream.Position = SearchPosition;

for (var i = SearchPosition; i <= br.BaseStream.Length; )
{
try
{
if (br.ReadByte() == 0x00)
{
if (br.ReadByte() == 0x00)
{
if (br.ReadByte() == 0x00)
{
if (br.ReadByte() == 0x70)
{
if (br.ReadByte() == 0x72)
{
if (br.ReadByte() == 0x6F)
{
if (br.ReadByte() == 0x6A)
{
byte[] Position = BitConverter.GetBytes(br.BaseStream.Position - 4); //-4 Because ive searched past my start mark and this is the position i NEED
Array.Reverse(Position);

output.AppendText("0x" + BitConverter.ToString(Position).Replace("00-00-00-00-0", "").Replace("-", "") + "\n"); //Offset Position Found
}
}
}
}
}
}
}
}
CATCH { break; }
}
MessageBox.Show("The application is done searching your file.", "Done", MessageBoxButtons.OK, MessageBoxIcon.Information);
br.Close();
}

This works and all but i need it to be usable for searching different things. I cant REALLY find any helpful info and i can figure it out for myself so im asking for your help.Alright so i came up with a new method of searching but the old one is like 4 times faster because it only needs to search up until something is invalid and doesn't have to track back, if you have a better way of doing this then let me know.
Code: [Select] void ByteArraySearcher()
{
byte[] SearchBytes = new byte[] { 0x00, 0x00, 0x00, 0x70, 0x72, 0x6F, 0x6A };
long SearchPosition = 0x00;

BinaryReader br = new BinaryReader(File.OpenRead(MapFile));
br.BaseStream.Position = SearchPosition;

for (var i = SearchPosition; i <= br.BaseStream.Length; i++)
{
byte[] ReadBytes = br.ReadBytes(SearchBytes.Length);
if (BitConverter.ToString(ReadBytes) == BitConverter.ToString(SearchBytes)) //Must convert both byte arrays to STRING to COMPARE correctly for some odd reason
{
byte[] Position = BitConverter.GetBytes(br.BaseStream.Position - SearchBytes);
Array.Reverse(Position);
output.AppendText(BitConverter.ToString(Position).Replace("00-00-00-00-0", "").Replace("-", "") + "\n");
}
else
{
br.BaseStream.Position = br.BaseStream.Position - SearchBytes.Length + 1; //Go forward 1 byte and search again
}
}
br.Close();
if (ShowMessage == true)
{
MessageBox.Show("The application is done searching your file.", "Done", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
}
Code: [Select] /// <summary>
/// Retrieves the first location of the specified sequence of bytes in the given stream.
/// </summary>
/// <param name="source">Stream to search.</param>
/// <param name="sequence">Sequence to look for.</param>
/// <returns>Byte position of the start of the first sequence.</returns>
private static long FindInStream(Stream source, byte[] sequence)
{
int byteposition;
if (sequence.Length == 0) return -1;
using (BinaryReader br = new BinaryReader(source))
{
try
{
while (true)
{
byte readbyte = br.ReadByte();
if (readbyte == sequence[0])
{
bool foundmatch = true;
for (int i = 1; i < sequence.Length; i++)
{
if (sequence[i] != br.ReadByte())
{
foundmatch = false;
break;
}
}
if (foundmatch) return br.BaseStream.Position - sequence.Length;
}
}
}
catch (EndOfStreamException exx)
{
return -1;
}
}
}
Quote from: BC_Programmer on April 17, 2014, 11:02:20 PM

Code: [Select] /// <summary>
/// Retrieves the first location of the specified sequence of bytes in the given stream.
/// </summary>
/// <param name="source">Stream to search.</param>
/// <param name="sequence">Sequence to look for.</param>
/// <returns>Byte position of the start of the first sequence.</returns>
private static long FindInStream(Stream source, byte[] sequence)
{
int byteposition;
if (sequence.Length == 0) return -1;
using (BinaryReader br = new BinaryReader(source))
{
try
{
while (true)
{
byte readbyte = br.ReadByte();
if (readbyte == sequence[0])
{
bool foundmatch = true;
for (int i = 1; i < sequence.Length; i++)
{
if (sequence[i] != br.ReadByte())
{
foundmatch = false;
break;
}
}
if (foundmatch) return br.BaseStream.Position - sequence.Length;
}
}
}
catch (EndOfStreamException exx)
{
return -1;
}
}
}

Why thank you good sir, while extremely fast, im finding myself sort from what im getting from my second method. There are 2 occurrences that this and my 1st post were not catching towards the end of my file and im not really sure why.