internal const int MAX_LENGTH = 255;        internal static readonly Regex NameRegex = new Regex("[;<>|\t]", RegexOptions.Compiled | RegexOptions.IgnoreCase);        internal static readonly Regex SpaceRegex = new Regex("[ ]{2,}", RegexOptions.Compiled | RegexOptions.IgnoreCase);        private string GetValidTermName(string name)        {            if (NameRegex.IsMatch(name))            {                name = NameRegex.Replace(name, " ");            }            name = SpaceRegex.Replace(name, " ");            name = name.Length > MAX_LENGTH ? name.Substring(0, MAX_LENGTH) : name;            name = name.Replace(Convert.ToChar(38), Convert.ToChar(65286));            return name.Trim();        }        private void WriteTagsToFolksonomyColumn(IEnumerable
     
       tags, SPListItem item, TaxonomyField column)        {            if (!column.IsTermSetValid) return;            if (!column.Open) return;            var session = new TaxonomySession(item.Web.Site);            var mms = session.TermStores[column.SspId];            var ts = mms.GetTermSet(column.TermSetId);            if (!ts.IsOpenForTermCreation) return;            var addedTerms = new List
      
       ();            bool hasChanges = false;            foreach (var tag in tags)            {                if (tag.Length > MAX_LENGTH) continue;                var validTag = GetValidTermName(tag);                Term matchingTerm=null;                if (column.IsKeyword)                {                    TermCollection terms = mms.GetTerms(validTag, false, StringMatchOption.ExactMatch, 1, true);                    if (terms.Count > 0)                        matchingTerm = terms[0];                }                else                {                    TermCollection terms = ts.GetTerms(validTag, false, StringMatchOption.ExactMatch, 1, true);                    if (terms.Count > 0)                        matchingTerm = terms[0];                }                if (matchingTerm == null)                {                    matchingTerm = ts.CreateTerm(validTag, mms.WorkingLanguage);                    hasChanges = true;                }                if (!addedTerms.Contains(matchingTerm))                {                    addedTerms.Add(matchingTerm);                }            }            if (hasChanges) mms.CommitAll();            if (addedTerms.Count > 0)            {                 if (column.AllowMultipleValues)                    column.SetFieldValue(item, addedTerms, mms.WorkingLanguage);                else                    column.SetFieldValue(item, addedTerms[0]);            }        }