1. The Different Systems
2. Any To Decimal
3. Decimal To Any
4. Any To Any
5. Roman Numerals

Comments

1. Mitch Dusina
   11 Sep 2007 at 04:29
   I have just returned from an extended absence from this forum so I realize this is rather late.
   
   It looks good, the only thing I can spot is the line where you catch the Exception.  Not finding an extended numeral is expected (and common at that), so an Exception shouldn't be used to control the flow of code.
   
   Although I can't think of an easy way around it since they removed Enum.TryParse (2.0 and later I think).
   
   
   
   
   
   
   
   
2. Peter McCombs
   24 May 2007 at 21:10
   Thanks for the Roman Numeral example! I made some equivalent functions in C# using Enum's static methods. This results in more concise versions of the two primary methods described in the article. They have been named a little bit differently to suit my tastes, but are the same methods in terms of the algorithm used. This code also uses the exact same RomanNumerals enum (which I haven't included in this snippet). Feel free to suggest further improvements, or to translate this back to VB.NET:
   
         
           private int ParseRomanNumeral(string numeral)
           {
               numeral = numeral.ToUpper();
   
               char[] characters = numeral.ToCharArray();
               int[] parseBuf = new int[numeral.Length];
               int result = 0;
               bool bSkip = false;
               for (int i = numeral.Length - 1; i >= 0; i--)
               {
                   if (bSkip)
                   {
                       bSkip = false; // Skip this digit because it is part of a 2-digit numeral
                       continue;
                   }
                   parseBuf[i] = (int)Enum.Parse(typeof(RomanNumerals), characters[i].ToString());
                   if (parseBuf[i] % 5 == 0 && i > 0)
                   {
                       string extended = characters[i-1].ToString() + characters[i].ToString();
                       try
                       {
                           parseBuf[i] = (int)Enum.Parse(typeof(RomanNumerals), extended);
                           bSkip = true;
                       }
                       catch(ArgumentException)
                       {
                           // Ignore this exception. It just means we didn't find an extended numeral
                       }
                   }
               }
   
               for (int i = 0; i < numeral.Length; i++)
               {
                   result += parseBuf[i];
               }
               return result;
           }
   
           private string ConvertToRomanNumeral(int num)
           {
               string sResult = "";
   
               sResult = Enum.GetName(typeof(RomanNumerals), num);
               if (sResult == null)
               {
                   string[] names = Enum.GetNames(typeof(RomanNumerals));
                   int[] vals = (int[])Enum.GetValues(typeof(RomanNumerals));
                   for (int i = names.Length - 1; i > 0; i--) // Don't process the 0th element, since it is 0 and results in bad math
                   {
                       int temp = num / vals[i];
                       num -= temp * vals[i];
                       for (int j = 0; j < temp; j++)
                       {
                           sResult += names[i];
                       }
                   }
               }
   
               return sResult;
           }
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
3. Developer Fusion Bot
   01 Jan 1999 at 00:00

   This thread is for discussions of Number Systems.