Я пишу класс строкового процессора. Вы можете использовать его.
Пример:
metaKeywords = bodyText.Process(blackListWords: prepositions).OrderByDescending().TakeTop().GetWords().AsString();
Класс:
public static class StringProcessor
{
private static List<String> PrepositionList;
public static string ToNormalString(this string strText)
{
if (String.IsNullOrEmpty(strText)) return String.Empty;
char chNormalKaf = (char)1603;
char chNormalYah = (char)1610;
char chNonNormalKaf = (char)1705;
char chNonNormalYah = (char)1740;
string result = strText.Replace(chNonNormalKaf, chNormalKaf);
result = result.Replace(chNonNormalYah, chNormalYah);
return result;
}
public static List<KeyValuePair<String, Int32>> Process(this String bodyText,
List<String> blackListWords = null,
int minimumWordLength = 3,
char splitor = ' ',
bool perWordIsLowerCase = true)
{
string[] btArray = bodyText.ToNormalString().Split(splitor);
long numberOfWords = btArray.LongLength;
Dictionary<String, Int32> wordsDic = new Dictionary<String, Int32>(1);
foreach (string word in btArray)
{
if (word != null)
{
string lowerWord = word;
if (perWordIsLowerCase)
lowerWord = word.ToLower();
var normalWord = lowerWord.Replace(".", "").Replace("(", "").Replace(")", "")
.Replace("?", "").Replace("!", "").Replace(",", "")
.Replace("<br>", "").Replace(":", "").Replace(";", "")
.Replace("،", "").Replace("-", "").Replace("\n", "").Trim();
if ((normalWord.Length > minimumWordLength && !normalWord.IsMemberOfBlackListWords(blackListWords)))
{
if (wordsDic.ContainsKey(normalWord))
{
var cnt = wordsDic[normalWord];
wordsDic[normalWord] = ++cnt;
}
else
{
wordsDic.Add(normalWord, 1);
}
}
}
}
List<KeyValuePair<String, Int32>> keywords = wordsDic.ToList();
return keywords;
}
public static List<KeyValuePair<String, Int32>> OrderByDescending(this List<KeyValuePair<String, Int32>> list, bool isBasedOnFrequency = true)
{
List<KeyValuePair<String, Int32>> result = null;
if (isBasedOnFrequency)
result = list.OrderByDescending(q => q.Value).ToList();
else
result = list.OrderByDescending(q => q.Key).ToList();
return result;
}
public static List<KeyValuePair<String, Int32>> TakeTop(this List<KeyValuePair<String, Int32>> list, Int32 n = 10)
{
List<KeyValuePair<String, Int32>> result = list.Take(n).ToList();
return result;
}
public static List<String> GetWords(this List<KeyValuePair<String, Int32>> list)
{
List<String> result = new List<String>();
foreach (var item in list)
{
result.Add(item.Key);
}
return result;
}
public static List<Int32> GetFrequency(this List<KeyValuePair<String, Int32>> list)
{
List<Int32> result = new List<Int32>();
foreach (var item in list)
{
result.Add(item.Value);
}
return result;
}
public static String AsString<T>(this List<T> list, string seprator = ", ")
{
String result = string.Empty;
foreach (var item in list)
{
result += string.Format("{0}{1}", item, seprator);
}
return result;
}
private static bool IsMemberOfBlackListWords(this String word, List<String> blackListWords)
{
bool result = false;
if (blackListWords == null) return false;
foreach (var w in blackListWords)
{
if (w.ToNormalString().Equals(word))
{
result = true;
break;
}
}
return result;
}
}