Procedural generation of cave-like maps for rogue-like games

This post is about procedural content generation of cave-like dungeons/maps for rogue-like games using what is known as the Cellular Automata method.

To understand what I mean by cellular automata method, imagine Conway's Game of Life. Many algorithms use what is called the '4-5 method', which means a tile will become a wall if it is a wall and 4 or more of its nine neighbors are walls, or if it is not a wall and 5 or more neighbors are walls. I start by filling the map randomly with walls or space, then visit each x/y position iteratively and apply the 4-5 rule. Usually this is preceded with 'seeding' the map by randomly filling each cell of the map with a wall or space, based on some weight (say, 40% of the time it chooses to place a wall). Then the automata step is applied multiple times over the entire map, precipitating walls and subsequently smoothing them. About 3 rounds is all that is required, with about 4-5 rounds being pretty typical amongst most implementations. Perhaps a picture of the the output will help you understand what I mean.

Using the automata-based method for procedural generation of levels will produce something similar to this:

Sure the dungeon generation by linking rooms approach has its place, but I really like the 'natural' look to the automata inspired method. I first originally discovered this technique on the website called Roguebasin. It is a great resource for information concerning the different problems involved with programming a rogue-like game, such as Nethack or Angband.

One of the major problems developers run into while employing this technique is the formation of isolated caves. Instead of one big cave-like room, you may get section of the map that is inaccessible without digging through walls. Isolated caves can trap key items or (worse) stairs leading to the next level, preventing further progress in the game. I have seen many different approaches proposed to solve this problem. Some suggestions I've seen include: 1) Discarding maps that have isolated caves, filling in the isolated sections, or finely tweaking the variables/rules to reduce occurrences of such maps. None of these are ideal (in my mind), and most require a way to detect isolated sections, which is another non-trivial problem in itself.

Despite this, I consider the problem solved because I have discovered a solution that is dead simple and almost** never fail because of the rules of the automata generation itself dictate such. I call my method 'Horizontal Blanking' because you can probably guess how it works now just from hearing the name. This step comes after the random filling of the map (initialization), but before the cellular automata iterations. After the map is 'seeded' with a random fill of walls, a horizontal strip in the middle of of the map is cleared of all walls. The horizontal strip is about 3 or 4 block tall (depending on rules). Clearing a horizontal strip of sufficient width will prevent a continuous vertical wall from being created and forming isolated caves in your maps. After horizontal blanking, you can begin applying the cellular automata method to your map.

** I say 'almost' because although it it not possible to get whole rooms that are disconnected from each other, it is possible to get tiny squares of blank space in the northern or southern walls that consist of about 4-5 blocks in total area. Often, these little holes will resolve themselves during the rounds of automata rules, but there still exists the possibility that one may persist. My answer to this edge case would be to use some rules around the placement of stairwells (and other must-find items) dictating that such objects must have a 2-3 block radius clear of walls to be placed.


See below for the code that produced the above screenshot, or click here to download the entire project with source code that you can compile yourself.

public class MapHandler
{
 Random rand = new Random();
 
 public int[,] Map;
 
 public int MapWidth   { get; set; }
 public int MapHeight  { get; set; }
 public int PercentAreWalls { get; set; }
 
 public MapHandler()
 {
  MapWidth = 40;
  MapHeight = 21;
  PercentAreWalls = 40;
  
  RandomFillMap();
 }

 public void MakeCaverns()
 {
  // By initilizing column in the outter loop, its only created ONCE
  for(int column=0, row=0; row <= MapHeight-1; row++)
  {
   for(column = 0; column <= MapWidth-1; column++)
   {
    Map[column,row] = PlaceWallLogic(column,row);
   }
  }
 }
 
 public int PlaceWallLogic(int x,int y)
 {
  int numWalls = GetAdjacentWalls(x,y,1,1);

  
  if(Map[x,y]==1)
  {
   if( numWalls >= 4 )
   {
    return 1;
   }
   return 0;   
  }
  else
  {
   if(numWalls>=5)
   {
    return 1;
   }
  }
  return 0;
 }
 
 public int GetAdjacentWalls(int x,int y,int scopeX,int scopeY)
 {
  int startX = x - scopeX;
  int startY = y - scopeY;
  int endX = x + scopeX;
  int endY = y + scopeY;
  
  int iX = startX;
  int iY = startY;
  
  int wallCounter = 0;
  
  for(iY = startY; iY <= endY; iY++) {
   for(iX = startX; iX <= endX; iX++)
   {
    if(!(iX==x && iY==y))
    {
     if(IsWall(iX,iY))
     {
      wallCounter += 1;
     }
    }
   }
  }
  return wallCounter;
 }
 
 bool IsWall(int x,int y)
 {
  // Consider out-of-bound a wall
  if( IsOutOfBounds(x,y) )
  {
   return true;
  }
  
  if( Map[x,y]==1  )
  {
   return true;
  }
  
  if( Map[x,y]==0  )
  {
   return false;
  }
  return false;
 }
 
 bool IsOutOfBounds(int x, int y)
 {
  if( x<0 data-blogger-escaped-else="" data-blogger-escaped-if="" data-blogger-escaped-return="" data-blogger-escaped-true="" data-blogger-escaped-x="" data-blogger-escaped-y="">MapWidth-1 || y>MapHeight-1 )
  {
   return true;
  }
  return false;
 }

Above is the main core of the logic.


Here is the rest of the program, such as filling, printing and blanking:

 
 public void PrintMap()
 {
  Console.Clear();
  Console.Write(MapToString());
 }
 
 string MapToString()
 {
  string returnString = string.Join(" ", // Seperator between each element
                                    "Width:",
                                    MapWidth.ToString(),
                                    "\tHeight:",
                                    MapHeight.ToString(),
                                    "\t% Walls:",
                                    PercentAreWalls.ToString(),
                                    Environment.NewLine
                                   );
  
  List<string> mapSymbols = new List();
  mapSymbols.Add(".");
  mapSymbols.Add("#");
  mapSymbols.Add("+");
  
  for(int column=0,row=0; row < MapHeight; row++ ) {
   for( column = 0; column < MapWidth; column++ )
   {
    returnString += mapSymbols[Map[column,row]];
   }
   returnString += Environment.NewLine;
  }
  return returnString;
 }
 
 public void BlankMap()
 {
  for(int column=0,row=0; row < MapHeight; row++) {
   for(column = 0; column < MapWidth; column++) {
    Map[column,row] = 0;
   }
  }
 }
 
 public void RandomFillMap()
 {
      // New, empty map
      Map = new int[MapWidth,MapHeight];
  
      int mapMiddle = 0; // Temp variable
      for(int column=0,row=0; row < MapHeight; row++) {
         for(column = 0; column < MapWidth; column++)
         {
       // If coordinants lie on the edge of the map
       // (creates a border)
       if(column == 0)
       {
      Map[column,row] = 1;
       }
       else if (row == 0)
       {
      Map[column,row] = 1;
       }
       else if (column == MapWidth-1)
       {
      Map[column,row] = 1;
       }
       else if (row == MapHeight-1)
       {
      Map[column,row] = 1;
       }
       // Else, fill with a wall a random percent of the time
       else
       {
      mapMiddle = (MapHeight / 2);
    
      if(row == mapMiddle)
      {
     Map[column,row] = 0;
      }
      else
      {
     Map[column,row] = RandomPercent(PercentAreWalls);
      }
       }
   }
      }
 }

 int RandomPercent(int percent)
 {
  if(percent>=rand.Next(1,101))
  {
   return 1;
  }
  return 0;
 }
 
 public MapHandler(int mapWidth, int mapHeight, int[,] map, int percentWalls=40)
 {
  this.MapWidth = mapWidth;
  this.MapHeight = mapHeight;
  this.PercentAreWalls = percentWalls;
  this.Map = new int[this.MapWidth,this.MapHeight];
  this.Map = map;
 }
}

And of course, the main function:

 
public static void Main(string[] args)
{
 char key  = new Char();
 MapHandler Map = new MapHandler();
 
 string instructions =
  "[Q]uit [N]ew [+][-]Percent walls [R]andom [B]lank" + Environment.NewLine +
  "Press any other key to smooth/step";

 Map.MakeCaverns();
 Map.PrintMap();
 Console.WriteLine(instructions);
 
 key = Char.ToUpper(Console.ReadKey(true).KeyChar);
 while(!key.Equals('Q'))
 {
  if(key.Equals('+')) {
   Map.PercentAreWalls+=1;
   Map.RandomFillMap();
   Map.MakeCaverns();
   Map.PrintMap();
  } else if(key.Equals('-')) {
   Map.PercentAreWalls-=1;
   Map.RandomFillMap();
   Map.MakeCaverns();
   Map.PrintMap();
  } else if(key.Equals('R')) {
   Map.RandomFillMap();
   Map.PrintMap();
  } else if(key.Equals('N')) {
   Map.RandomFillMap();
   Map.MakeCaverns();
   Map.PrintMap();
  } else if(key.Equals('B')) {
   Map.BlankMap();
   Map.PrintMap();
  } else if(key.Equals('D')) {
   // I set a breakpoint here...
  } else {
   Map.MakeCaverns();
   Map.PrintMap();
  }
  Console.WriteLine(instructions);
  key = Char.ToUpper(Console.ReadKey(true).KeyChar);
 }
 Console.Clear();
 Console.Write(" Thank you for playing!");
 Console.ReadKey(true);
}

See also: Roguebasin - Cellular Automata Method for Generating Random Cave-Like Levels

XML Serializable Dictionary, Tuple, and Object

Serializing a data class to an XML file using XmlSerializer is very useful. However, some of the most useful data classes in .NET are not serializable. Dictionary and Tuple most notably. If you looking for a blog post on how to make a Dictionary that accepts duplicate keys by storing the values values with identical keys in a List, please see this blog post.

The below SerializableDictionary class works by inheriting from IXmlSerializable, which requires you implement the following three methods:
* GetSchema() - Remember, you should always return null for this function.
* ReadXml(XmlReader reader)
* WriteXml(XmlWriter writer)
(Read about IXmlSerializable on MSDN)

Here is the code to serialize a dictionary or serialize a tuple:

namespace XMLSerializableDictionary
{
    using System;
    using System.Collections.Generic;
    using System.Runtime.Serialization;
    using System.Xml;
    using System.Xml.Schema;
    using System.Xml.Serialization;

     [Serializable]
    [XmlRoot("Dictionary")]
    public class SerializableDictionary<TKey, TValue>
        : Dictionary<TKey, TValue>, IXmlSerializable
    {
        private const string DefaultTagItem = "Item";
        private const string DefaultTagKey = "Key";
        private const string DefaultTagValue = "Value";
        private static readonly XmlSerializer KeySerializer =
                                        new XmlSerializer(typeof(TKey));

        private static readonly XmlSerializer ValueSerializer =
                                        new XmlSerializer(typeof(TValue));

        public SerializableDictionary() : base()
        {
        }

        protected SerializableDictionary(SerializationInfo info, StreamingContext context)
                : base(info, context)
        {
        }

        protected virtual string ItemTagName
        {
            get { return DefaultTagItem; }
        }

        protected virtual string KeyTagName
        {
            get { return DefaultTagKey; }
        }

        protected virtual string ValueTagName
        {
            get { return DefaultTagValue; }
        }

        public XmlSchema GetSchema()
        {
            return null;
        }

        public void ReadXml(XmlReader reader)
        {
            bool wasEmpty = reader.IsEmptyElement;

            reader.Read();

            if (wasEmpty)
            {
             return;
            }

            try
            {
                while (reader.NodeType != XmlNodeType.EndElement)
                {
                    reader.ReadStartElement(this.ItemTagName);
                    try
                    {
                        TKey tKey;
                        TValue tValue;

                        reader.ReadStartElement(this.KeyTagName);
                        try
                        {
                            tKey = (TKey)KeySerializer.Deserialize(reader);
                        }
                        finally
                        {
                            reader.ReadEndElement();
                        }

                        reader.ReadStartElement(this.ValueTagName);
                        try
                        {
                            tValue = (TValue)ValueSerializer.Deserialize(reader);
                        }
                        finally
                        {
                            reader.ReadEndElement();
                        }

                        this.Add(tKey, tValue);
                    }
                    finally
                    {
                        reader.ReadEndElement();
                    }

                    reader.MoveToContent();
                }
            }
            finally
            {
                reader.ReadEndElement();
            }
        }

        public void WriteXml(XmlWriter writer)
        {
            foreach (KeyValuePair<TKey, TValue> keyValuePair in this)
            {
                writer.WriteStartElement(this.ItemTagName);
                try
                {
                    writer.WriteStartElement(this.KeyTagName);
                    try
                    {
                        KeySerializer.Serialize(writer, keyValuePair.Key);
                    }
                    finally
                    {
                        writer.WriteEndElement();
                    }

                    writer.WriteStartElement(this.ValueTagName);
                    try
                    {
                        ValueSerializer.Serialize(writer, keyValuePair.Value);
                    }
                    finally
                    {
                        writer.WriteEndElement();
                    }
                }
                finally
                {
                    writer.WriteEndElement();
                }
            }
        }
    }
}

The idea behind the serializable tuple is we just make our own Tuple that stores the items by declaring the properties to represent them with their generic T type. If you are not used to working with generics, this can be a little strange. T1, T2 and T3 are just placeholders for the type that is to be determined by the calling function, or the function above that if the calling function uses generics too.

And a serializable tuple:

public class SerializableTuple<T1,T2,T3>
{
 public T1 Item1 { get; set; }
 public T2 Item2 { get; set; }
 public T3 Item3 { get; set; }
 
 public static implicit operator Tuple<T1,T2,T3>(SerializableTuple<T1,T2,T3>  st)
 {
  return Tuple.Create(st.Item1,st.Item2,st.Item3);
 }

 public static implicit operator SerializableTuple<T1,T2,T3>(Tuple<T1,T2,T3> t)
 {
  return new SerializableTuple<T1,T2,T3>() {
   Item1 = t.Item1,
   Item2 = t.Item2,
   Item3 = t.Item3
  };   
 }
 
 public SerializableTuple()
 {
 }
}

And finally, a generic object serializer and deserializer:

public static class XML
{
   public static class Serialize
   {
      public static void Object(string Filename, object obj)
      {
         using (StreamWriter streamWriter = new StreamWriter(Filename))
         {
            XmlSerializer xmlSerializer = new XmlSerializer(obj.GetType());
            xmlSerializer.Serialize(streamWriter, obj);
         }
      }
   }

   public static class DeSerialize
   {
      public static string Generic<T>(T data)
      {
         if (data == null)
            return string.Empty;

         string content = string.Empty;
         using (MemoryStream memoryStream = new MemoryStream())
         {
            XmlSerializer serializer = new XmlSerializer(typeof(T));
            serializer.Serialize(memoryStream, data);

            memoryStream.Seek(0, SeekOrigin.Begin);
            using (StreamReader reader = new StreamReader(memoryStream))
            {
               content = reader.ReadToEnd();
            }
         }
         return content;
      }

      public static object Object(string Filename, Type type)
      {
         object result = null;
         using (TextReader reader = new StringReader(Filename))
         {
            XmlSerializer serializer = new XmlSerializer(type);
            result = serializer.Deserialize(reader);
         }
         return result;
      }
   }
}

And perhaps after you serialize your data to an XML file, you would like to generate a schema XML file from it:

  
void XmlToSchema(string FileName)
{
 XmlReader xmlReader = XmlReader.Create(FileName);
 XmlSchemaSet schemaSet = new XmlSchemaSet();
 XmlSchemaInference schemaInfer = new XmlSchemaInference();
 schemaSet = schemaInfer.InferSchema(xmlReader);

 string outFilename = Path.ChangeExtension(FileName,".xsd");
 using(Stream streamOut = new FileStream(outFilename,FileMode.Create) )
 {
  TextWriter textWriter =  new StreamWriter(streamOut);    
  foreach (XmlSchema s in schemaSet.Schemas())
  {
   s.Write(textWriter );
  }
  textWriter .Close();
 }
}

PeriodicTable Element Class

Periodic Table as an Array of class Element in C#

public class Element
{
    public int AtomicNumber { get; set; }
    public string Symbol { get; set; }
    public string Name { get; set; }
    public decimal AtomicWeight { get; set; }
//  public string GroupNumber { get; set; }
//  public string GroupName { get; set; }
//  public string Period { get; set; }
//  public string Block { get; set; }
//  public string CASRegistryID { get; set; }
//  public string DiscoveryDate { get; set; }
//  public string DiscovererName { get; set; }
    
    public Element() { }
    public Element(int atomicNumber,string symbol,string name,decimal atomicWeight)
    {
        AtomicNumber = atomicNumber;
        Symbol = symbol;
        Name = name;
        AtomicWeight = atomicWeight;
    }
}

public class PeriodicTable
{
    public List<element> Elements;

    public PeriodicTable()
    {
        Elements = new List();
        Elements.Add(new Element(1,     "H",    "Hydrogen",     1.007825M ));
        Elements.Add(new Element(2,     "He",   "Helium",       4.00260M  ));
        Elements.Add(new Element(3,     "Li",   "Lithium",      6.941M    ));
        Elements.Add(new Element(4,     "Be",   "Beryllium",    9.01218M  ));
        Elements.Add(new Element(5,     "B",    "Boron",        10.81M    ));
        Elements.Add(new Element(6,     "C",    "Carbon",       12.011M   ));
        Elements.Add(new Element(7,     "N",    "Nitrogen",     14.0067M  ));
        Elements.Add(new Element(8,     "O",    "Oxygen",       15.999M   ));
        Elements.Add(new Element(9,     "F",    "Fluorine",     18.99840M ));
        Elements.Add(new Element(10,    "Ne",   "Neon",         20.179M   ));
        Elements.Add(new Element(11,    "Na",   "Sodium",       22.98977M ));
        Elements.Add(new Element(12,    "Mg",   "Magnesium",    24.305M   ));
        Elements.Add(new Element(13,    "Al",   "Aluminum",     26.98154M ));
        Elements.Add(new Element(14,    "Si",   "Silicon",      28.0855M  ));
        Elements.Add(new Element(15,    "P",    "Phosphorus",   0.0M      ));
        Elements.Add(new Element(16,    "S",    "Sulphur",      32.06M    ));
        Elements.Add(new Element(17,    "Cl",   "Chlorine",     35.453M   ));
        Elements.Add(new Element(18,    "Ar",   "Argon",        39.948M   ));
        Elements.Add(new Element(19,    "K",    "Potassium",    39.0983M  ));
        Elements.Add(new Element(20,    "Ca",   "Calcium",      40.08M    ));
        Elements.Add(new Element(21,    "Sc",   "Scandium",     44.9559M  ));
        Elements.Add(new Element(22,    "Ti",   "Titanium",     47.90M    ));
        Elements.Add(new Element(23,    "V",    "Vanadium",     50.9414M  ));
        Elements.Add(new Element(24,    "Cr",   "Chromium",     51.996M   ));
        Elements.Add(new Element(25,    "Mn",   "Manganese",    54.9380M  ));
        Elements.Add(new Element(26,    "Fe",   "Iron",         55.85M    ));
        Elements.Add(new Element(27,    "Co",   "Cobalt",       58.9332M  ));
        Elements.Add(new Element(28,    "Ni",   "Nickel",       58.71M    ));
        Elements.Add(new Element(29,    "Cu",   "Copper",       63.546M   ));
        Elements.Add(new Element(30,    "Zn",   "Zinc",         65.37M    ));
        Elements.Add(new Element(31,    "Ga",   "Gallium",      69.72M    ));
        Elements.Add(new Element(32,    "Ge",   "Germanium",    72.59M    ));
        Elements.Add(new Element(33,    "As",   "Arsenic",      74.9216M  ));
        Elements.Add(new Element(34,    "Se",   "Selenium",     78.96M    ));
        Elements.Add(new Element(35,    "Br",   "Bromine",      79.904M   ));
        Elements.Add(new Element(36,    "Kr",   "Krypton",      83.80M    ));
        Elements.Add(new Element(37,    "Rb",   "Rubidium",     85.4678M  ));
        Elements.Add(new Element(38,    "Sr",   "Strontium",    87.62M    ));
        Elements.Add(new Element(39,    "Y",    "Yttrium",      88.9059M  ));
        Elements.Add(new Element(40,    "Zr",   "Zirconium",    91.22M    ));
        Elements.Add(new Element(41,    "Nb",   "Niobium",      92.91M    ));
        Elements.Add(new Element(42,    "Mo",   "Molybdenum",   95.94M    ));
        Elements.Add(new Element(43,    "Tc",   "Technetium",   99.0M     ));
        Elements.Add(new Element(44,    "Ru",   "Ruthenium",    101.1M    ));
        Elements.Add(new Element(45,    "Rh",   "Rhodium",      102.91M   ));
        Elements.Add(new Element(46,    "Pd",   "Palladium",    106.42M   ));
        Elements.Add(new Element(47,    "Ag",   "Silver",       107.87M   ));
        Elements.Add(new Element(48,    "Cd",   "Cadmium",      112.4M    ));
        Elements.Add(new Element(49,    "In",   "Indium",       114.82M   ));
        Elements.Add(new Element(50,    "Sn",   "Tin",          118.69M   ));
        Elements.Add(new Element(51,    "Sb",   "Antimony",     121.75M   ));
        Elements.Add(new Element(52,    "Te",   "Tellurium",    127.6M    ));
        Elements.Add(new Element(53,    "I",    "Iodine",       126.9045M ));
        Elements.Add(new Element(54,    "Xe",   "Xenon",        131.29M   ));
        Elements.Add(new Element(55,    "Cs",   "Cesium",       132.9054M ));
        Elements.Add(new Element(56,    "Ba",   "Barium",       137.33M   ));
        Elements.Add(new Element(57,    "La",   "Lanthanum",    138.91M   ));
        Elements.Add(new Element(58,    "Ce",   "Cerium",       140.12M   ));
        Elements.Add(new Element(59,    "Pr",   "Praseodymium", 140.91M   ));
        Elements.Add(new Element(60,    "Nd",   "Neodymium",    0.0M      ));
        Elements.Add(new Element(61,    "Pm",   "Promethium",   147.0M    ));
        Elements.Add(new Element(62,    "Sm",   "Samarium",     150.35M   ));
        Elements.Add(new Element(63,    "Eu",   "Europium",     167.26M   ));
        Elements.Add(new Element(64,    "Gd",   "Gadolinium",   157.25M   ));
        Elements.Add(new Element(65,    "Tb",   "Terbium",      158.925M  ));
        Elements.Add(new Element(66,    "Dy",   "Dysprosium",   162.50M   ));
        Elements.Add(new Element(67,    "Ho",   "Holmium",      164.9M    ));
        Elements.Add(new Element(68,    "Er",   "Erbium",       167.26M   ));
        Elements.Add(new Element(69,    "Tm",   "Thulium",      168.93M   ));
        Elements.Add(new Element(70,    "Yb",   "Ytterbium",    173.04M   ));
        Elements.Add(new Element(71,    "Lu",   "Lutetium",     174.97M   ));
        Elements.Add(new Element(72,    "Hf",   "Hafnium",      178.49M   ));
        Elements.Add(new Element(73,    "Ta",   "Tantalum",     180.95M   ));
        Elements.Add(new Element(74,    "W",    "Tungsten",     183.85M   ));
        Elements.Add(new Element(75,    "Re",   "Rhenium",      186.23M   ));
        Elements.Add(new Element(76,    "Os",   "Osmium",       190.2M    ));
        Elements.Add(new Element(77,    "Ir",   "Iridium",      192.2M    ));
        Elements.Add(new Element(78,    "Pt",   "Platinum",     195.09M   ));
        Elements.Add(new Element(79,    "Au",   "Gold",         196.9655M ));
        Elements.Add(new Element(80,    "Hg",   "Mercury",      200.59M   ));
        Elements.Add(new Element(81,    "Tl",   "Thallium",     204.383M  ));
        Elements.Add(new Element(82,    "Pb",   "Lead",         207.2M    ));
        Elements.Add(new Element(83,    "Bi",   "Bismuth",      208.9804M ));
        Elements.Add(new Element(84,    "Po",   "Polonium",     210.0M    ));
        Elements.Add(new Element(85,    "At",   "Astatine",     210.0M    ));
        Elements.Add(new Element(86,    "Rn",   "Radon",        222.0M    ));
        Elements.Add(new Element(87,    "Fr",   "Francium",     233.0M    ));
        Elements.Add(new Element(88,    "Ra",   "Radium",       226.0254M ));
        Elements.Add(new Element(89,    "Ac",   "Actinium",     227.0M    ));
        Elements.Add(new Element(90,    "Th",   "Thorium",      232.04M   ));
        Elements.Add(new Element(91,    "Pa",   "Protactinium", 231.0359M ));
        Elements.Add(new Element(92,    "U",    "Uranium",      238.03M   ));
        Elements.Add(new Element(93,    "Np",   "Neptunium",    237.0M    ));
        Elements.Add(new Element(94,    "Pu",   "Plutonium",    244.0M    ));
        Elements.Add(new Element(95,    "Am",   "Americium",    243.0M    ));
        Elements.Add(new Element(96,    "Cm",   "Curium",       247.0M    ));
        Elements.Add(new Element(97,    "Bk",   "Berkelium",    247.0M    ));
        Elements.Add(new Element(98,    "Cf",   "Californium",  251.0M    ));
        Elements.Add(new Element(99,    "Es",   "Einsteinium",  254.0M    ));
        Elements.Add(new Element(100,   "Fm",   "Fermium",      257.0M    ));
        Elements.Add(new Element(101,   "Md",   "Mendelevium",  258.0M    ));
        Elements.Add(new Element(102,   "No",   "Nobelium",     259.0M    ));
        Elements.Add(new Element(103,   "Lr",   "Lawrencium",   262.0M    ));
        Elements.Add(new Element(104,   "Rf",   "Rutherfordium",260.9M    ));
        Elements.Add(new Element(105,   "Db",   "Dubnium",      261.9M    ));
        Elements.Add(new Element(106,   "Sg",   "Seaborgium",   262.94M   ));
        Elements.Add(new Element(107,   "Bh",   "Bohrium",      262.0M    ));
        Elements.Add(new Element(108,   "Hs",   "Hassium",      264.8M    ));
        Elements.Add(new Element(109,   "Mt",   "Meitnerium",   265.9M    ));
        Elements.Add(new Element(110,   "Ds",   "Darmstadtium", 261.9M    ));
        Elements.Add(new Element(112,   "Uub",  "Ununbium",     276.8M    ));
        Elements.Add(new Element(114,   "Uuq",  "Ununquadium",  289.0M    ));
        Elements.Add(new Element(116,   "Uuh",  "Ununhexium",   0.0M      ));
    }
}

Improvements could include implementing a the PeriodicTable as a Dictionary, such as a Dictionary<string,Element>. This adds the ability to to retrieve Element information given only its symbol or atomic number. Use SortedDictionary<string,Element> to order the elements by symbol, name, atomic number or weight (the dictionary will be sorted off of the key).


Admittedly, this still isn't a very useful class, its just for fun.

Fake/Random Identity Generator

Inspiration

During my research on RSA cryptography and the importance of a truly random number for having a large key-space, I stumbled on to FakeNameGenerator.com. I thought the concept could be really useful for certain applications and could easily envision how to implement it in C#, and make it extensible/customizable.

Take a look at these:

<?xml version="1.0" standalone="yes"?>
<DocumentElement>
  <Order>
    <Date>3/18/2005</Date>
    <TrackingNumber>1Z 8A8 238 01 9398 182 1</TrackingNumber>
    <FirstName>Keaton </FirstName>
    <LastName>Day</LastName>
    <StreetAddress>4828 Cherry St.</StreetAddress>
    <City>Nanticoke</City>
    <State>SC</State>
    <Zip>89130</Zip>
    <Email>HaleHale8026@mail.com</Email>
    <Phone>425-765-4520</Phone>
  </Order>

  <Payroll>
    <PhoneNumber>971-258-5703</PhoneNumber>
    <AltPhoneNumber>501-769-1331</AltPhoneNumber>
    <FirstName>Xyla </FirstName>
    <LastName>Hoover</LastName>
    <EmployeeID>499</EmployeeID>
    <HireDate>5/28/2011</HireDate>
    <Birthdate>5/28/1990</Birthdate>
    <SSN>520-52-4275</SSN>
    <AccountNumber>5696618825</AccountNumber>
    <RoutingNumber>575159859</RoutingNumber>
    <Address>8348 Court Ave.</Address>
    <City>Pittsburgh,</City>
    <State>PA.</State>
    <Zip>15201</Zip>
  </Payroll>

 CREATE TABLE ReservationData (
  `id` mediumint(8) unsigned NOT NULL auto_increment,
  `UniqueID` MEDIUMINT default NULL,
  `TripDate` varchar(50) default NULL,
  `FirstName` varchar(255) default NULL,
  `LastName` varchar(255) default NULL,
  `Phone` varchar(100) default NULL,
  `AltPhone` varchar(100) default NULL,
  `Email` varchar(255) default NULL,
  `StreetAddress` varchar(255) default NULL,
  `City` varchar(50) default NULL,
  `State` varchar(50) default NULL,
  `Zip` varchar(10) default NULL,
  `Country` varchar(255) default NULL,
  `DayOfYear` varchar(50) default NULL,
  `TotalCost` varchar(50) default NULL,
  `Balance` varchar(10) default NULL,
  `CCard` varchar(18) default NULL,
  `Expires` varchar(5) default NULL,
  `CVC2` varchar(3) default NULL,
  PRIMARY KEY (`id`)
) TYPE=MyISAM AUTO_INCREMENT=1;

This would make great honey for a honey pot; just fill an SQL database with this random, realistic looking data, serve and log any and all attempts to access, query or dump the database. This can be done on a VM and you have a easily deployed, high interaction honeypot!

Aside from being able to see their IP address, I think the most useful data that can be attained is their behavior; what injection attacks are they using to drop the database? Write rules to prevent your honey against trivial attempts such as the ' AND 1=(SELECT attacks and see what they come up with next. Rule writing is inherently a cat-and-mouse game, honeypots like this clearly give the white-hats the upper hand.

Implementation

A quick, fast and dirty solution is to simply read a random line from a text file (i.e. Name_First.txt and Address_Street.txt).

This way, you can choose from names that are common, or customize your list to for different nationalities.

One could read the whole file in to a string, Parse() it into an array of strings, then randomly select an index, but this would be unacceptable for very large files. Instead, we can set the file pointer to a random position that is less than its size, roll back to the last new line and call ReadLine.

public string ReturnRandomLine(string FileName)
{
 string sReturn = string.Empty;
 
 using(FileStream myFile = new FileStream(FileName,FileMode.Open,FileAccess.Read))
 {
  using(StreamReader myStream = new StreamReader(myFile))
  {
   // Seek file stream pointer to a rand position...
   myStream.BaseStream.Seek(rand.Next(1,myFile.Length),SeekOrigin.Begin);
   
   // Read the rest of that line.
   myStream.ReadLine();
   
   // Return the next, full line...
   sReturn = myStream.ReadLine();
  }
 }
 
 // If our random file position was too close to the end of the file, it will return an empty string
 // I avoided a while loop in the case that the file is empty or contains only one line
 if(System.String.IsNullOrWhiteSpace(sReturn)) {
  sReturn = ReturnRandomLine(FileName);
 }
 
 return sReturn;
}

Example use:

public string GenerateFistName()
{
 return ReturnRandomLine("Name_First.txt") + " ";
}

public string GenerateLastName()
{
 return ReturnRandomLine("Name_Last.txt");
}

public string GenerateFullName()
{
 return GenerateFistName() + GenerateLastName();
}

public string GenerateGender()
{
 if(ReturnPercent(84)) {
  return "Male";
 } else {
  return "Female";
 }
}

public string GenerateStreetNumber()
{
 return rand.Next(1,9999).ToString();
}

public string GenerateStreetName()
{
 return ReturnRandomLine("Address_Street.txt");
}

One limitation is where the data is relational, such as in the case of generating a random zip code along with the city and state that it exists in.

A quick work-around would be CityZipState.txt



Other types of data that can be generated that would not make sense to put in a text file:

public bool ReturnPercent(int Percent) // Return true Percent times out of 100, randomly
{
 int iTemp = rand.Next(1,101);
 
 if(iTemp<=Percent) {
  return true;
 } else {
  return false;
 }
}

public string GenerateDate(int YearFrom,int YearTo)
{
 int Month = rand.Next(1,13);
 int Day  = rand.Next(1,32);
 int Year = GenerateYear(YearFrom,YearTo);
 
 return Month.ToString() + "/" + Day.ToString() + "/" + Year.ToString();
}

public string GenerateYear(int YearFrom,int YearTo)
{
 return rand.Next(YearFrom,YearTo+1).ToString();
}

public string GeneratePhoneNumber()
{
 return GeneratePhoneNumber(ReturnRandomLine("PhoneNumber_Prefix.txt"));
}

public string GeneratePhoneNumber(string Prefix)
{
 int iThree = rand.Next(192,999);
 int iFour = rand.Next(1000,9999);
 
 return Prefix + iThree.ToString() + "-" + iFour.ToString();
}

public string GenerateSSN()
{
 int iThree = rand.Next(132,921);
 int iTwo = rand.Next(12,83);
 int iFour = rand.Next(1423,9211);
 return iThree.ToString() + "-" + iTwo.ToString() + "-" + iFour.ToString();
}

Obviously, these methods can be improved to conform to the standards of a real social security number, national identification number, credit card number, ect...

public string GenerateCCNum()
{
 string sCCNum = string.Empty;
 
 byte[] bCCNum = {0};
 rand.NextBytes(bCCNum);
 
 // generate random 16 digit number
 int iTemp1 = rand.Next(10000000,99999999);
 int iTemp2 = rand.Next(10000000,99999999);
 string sTemp = iTemp1.ToString() + iTemp2.ToString();
 
 // while loop?
 while(!IsValidNumber(sTemp))
 {
  iTemp1 = rand.Next(10000000,99999999);
  iTemp2 = rand.Next(10000000,99999999);
  sTemp = iTemp1.ToString() + iTemp2.ToString();
 }
 
 sCCNum = sTemp;
 
 return sCCNum;
}

The implementation of IsValidNumber() is left as an exercise for the reader.

The serialization of your data is a trivial matter. Please see my post on a XML Serializable Dictionary, Tuple, and Object for the code to serialize an object (such as a list, or a class).

Gracefull error handling with a global exception handler

Every published C# application should have graceful error handling. Here I show you the implementation of a global exception handler using ThreadExceptionEventHandler.

First, you have to add System.Threading to both your Program.cs and Mainform.cs:

// Program.cs and Mainform.cs
using System.Threading;

Then add an event handler to Application.ThreadException:

// Program.cs
// static class Program {
//  private static void Main(string[] args) {
Application.ThreadException += new ThreadExceptionEventHandler(MainForm.MyExceptionHandler);
// Application.Run(new MainForm());

Or, if you are writing a console app, add an event handler to AppDomain.UnhandledException:
AppDomain.CurrentDomain.UnhandledException += new UnhandledExceptionEventHandler(MyExceptionHandler);

Then add the exception handler body:

// Mainform.cs
public static void MyExceptionHandler(object sender, ThreadExceptionEventArgs e)
{
   MessageBox.Show(e.Exception.Message,"Error",MessageBoxButtons.OK,MessageBoxIcon.Error);
}

The example here simply shows a message box, but an even more graceful approach would be to log all the unhanded exceptions to a log file. That way, the errors are transparent to the user, but the developer still has access to detailed debug information.

Here is the full code:
Program.cs
MainForm.cs