public override string BuildKey(string word)
{
if (string.IsNullOrEmpty(word))
{
return(string.Empty);
}
string upperName = word.ToUpper();
//Let's strip non A-Z characters
upperName = Regex.Replace(upperName, "[^A-Z]", string.Empty, RegexOptions.Compiled);
//step 1
TranslateFirstCharacters(ref upperName);
//step 2
TranslateLastCharacters(ref upperName);
//step 3
string firstCharacter = upperName.Substring(0, 1);
string remainingName = upperName.Length > 1 ? upperName.Substring(1) : string.Empty;
if (!string.IsNullOrEmpty(remainingName.Trim()))
{
//step 4
TranslateRemaining(ref remainingName);
//step 6 - 8
ReplaceLastCharacter(ref remainingName);
}
//collapse repeating characters and append first character back on
return(firstCharacter + SioHelpers.CollapseAdjacentRepeating(remainingName));
}
internal static string CollapseRepeatingConsonants(string name)
{
StringBuilder sb = new StringBuilder();
char prev = ' ';
bool first = true;
foreach (char c in name)
{
if (c != prev || first || SioHelpers.IsVowel(c))
{
sb.Append(c);
first = false;
}
prev = c;
}
return(sb.ToString());
}
public static void GenerateNysiisKey(string name, out string key, out string fullKey)
{
key = string.Empty;
fullKey = string.Empty;
if (string.IsNullOrEmpty(name))
{
return;
}
string upperName = name.ToUpper();
//Let's strip non A-Z characters
upperName = Regex.Replace(upperName, "[^A-Z]", string.Empty, RegexOptions.Compiled);
//step 1
TranslateFirstCharacters(ref upperName);
//step 2
TranslateLastCharacters(ref upperName);
//step 3
string firstCharacter = upperName.Substring(0, 1);
string remainingName = upperName.Length > 1 ? upperName.Substring(1) : string.Empty;
if (!string.IsNullOrEmpty(remainingName.Trim()))
{
//step 4
TranslateRemaining(ref remainingName);
//step 6 - 8
ReplaceLastCharacter(ref remainingName);
}
//collapse repeating characters and append first character back on
fullKey = firstCharacter + SioHelpers.CollapseAdjacentRepeating(remainingName);
//a true NYSIIS key is only 6 characters long
key = fullKey.Substring(0, (fullKey.Length >= 6 ? 6 : fullKey.Length));
}
public int MatchRatingCompute(string name1, string name2)
{
//0 is an impossible rating, it will mean unrated
if (string.IsNullOrEmpty(name1) || string.IsNullOrEmpty(name2))
{
return(0);
}
string large;
string small;
if (name1.Length >= name2.Length)
{
large = name1.ToUpper();
small = name2.ToUpper();
}
else
{
large = name2.ToUpper();
small = name1.ToUpper();
}
int x = large.Length;
int y = small.Length;
//If the length difference between the encoded strings is 3 or greater, then no similarity comparison is done.
if ((x - y) > 3)
{
return(0);
}
//Obtain the minimum rating value by calculating the length sum of the encoded strings and using table A
int minRating = MinimumRating(x + y);
//Process the encoded strings from left to right and remove any identical characters found from both strings respectively.
for (int i = 0; i < small.Length;)
{
bool found = false;
for (int j = 0; j < large.Length; j++)
{
if (small[i] == large[j])
{
small = small.Remove(i, 1);
large = large.Remove(j, 1);
found = true;
}
}
if (!found)
{
i++;
}
}
large = SioHelpers.ReverseString(large);
small = SioHelpers.ReverseString(small);
//Process the unmatched characters from right to left and remove any identical characters found from both names respectively.
for (int i = 0; i < small.Length;)
{
bool found = false;
for (int j = 0; j < large.Length; j++)
{
if (small[i] == large[j])
{
small = small.Remove(i, 1);
large = large.Remove(j, 1);
found = true;
}
}
if (!found)
{
i++;
}
}
//Subtract the number of unmatched characters from 6 in the longer string. This is the similarity rating.
int rating = 6 - (large.Length);
//If the similarity rating equal to or greater than the minimum rating then the match is considered good.
if (rating >= minRating)
{
return(rating);
}
return(0);
}
