HexPattern.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ProcessMemory
{
    public class HexPattern : IMemoryPattern
    {
        public string[] Pattern { get; private set; }
        public byte?[] PatternBytes { get; private set; }

        public long Length => PatternBytes.Length;

        public HexPattern(string pattern) {
            //Split pattern into an array for each space.
            Pattern = pattern.Split(' ');

            byte?[] bytes = new byte?[Pattern.Length];

            //Loop through each pattern string
            for (int i = 0; i < Pattern.Length; i++) {
                //If pattern at index is == ?? then we set that byte to null
                if (Pattern[i].Equals("??"))
                {
                    bytes[i] = null;
                }
                else
                {
                    bytes[i] = Convert.ToByte(Pattern[i], 16);
                }
                //If pattern is not == ?? then convert it to a byte
            }
            PatternBytes = bytes;
        }

        public long FindMatch(byte[] source, long length) {
            bool allTheSame;
            for (int i = 0; i + PatternBytes.Length <= length; i++) {
                allTheSame = true;
                for (int jj = 0; jj < PatternBytes.Length; jj++) {
                    if (PatternBytes[jj] == null)
                        continue;

                    if (source[i + jj] != PatternBytes[jj]) {
                        allTheSame = false;
                        break;
                    }
                }

                if (allTheSame)
                    return i;
            }

            return -1;
        }
    }
}