public static RangeSet Split(this IWordSplitter splitter, ByteBlock text)
{
RangeSet words = new RangeSet();
splitter.Split(text.Array, new Range(text.Index, text.Length), words);
return(words);
}
public ByteBlock Highlight(ByteBlock value, IWordSplitter splitter, List <HighlightTerm> terms)
{
if (terms == null)
{
throw new ArgumentNullException("terms");
}
if (splitter == null)
{
throw new ArgumentNullException("splitter");
}
ByteBlockAppender appender = new ByteBlockAppender(value);
// Make a lowercase value copy to compare
ByteBlock valueLower = value.Copy();
valueLower.ToLowerInvariant();
// Split the value and compare words to highlight terms
RangeSet ranges = splitter.Split(valueLower);
for (int rangeIndex = 0; rangeIndex < ranges.Count; ++rangeIndex)
{
Range r = ranges.Ranges[rangeIndex];
ByteBlock valueWord = new ByteBlock(valueLower.Array, r.Index, r.Length);
foreach (HighlightTerm term in terms)
{
// If this word in the value starts with a search term...
if (term.Matches(valueWord))
{
// Append to the beginning of the word, if not already past this point
if (appender.AppendTo(valueWord.Index))
{
// Wrap and append the *prefix* of the term from the query
appender.Append(_wrapPrefix);
appender.AppendTo(valueWord.Index + term.Value.Length);
appender.Append(_wrapSuffix);
}
// If we matched, do not check other HighlightTerms against this word
break;
}
}
}
// Append the remaining content and return
appender.AppendRemainder();
return(appender.Value());
}
public static List <HighlightTerm> WordsForColumn(IExpression where, string columnName, IWordSplitter splitter)
{
List <HighlightTerm> terms = new List <HighlightTerm>();
// For each term in the query expression...
IList <TermExpression> matchingTerms = where.GetAllTerms(columnName);
foreach (TermExpression term in matchingTerms)
{
ByteBlock termValue;
if (term.Value.TryConvert <ByteBlock>(out termValue))
{
ByteBlock termValueLower = termValue.Copy();
termValueLower.ToLowerInvariant();
if (term.Operator == Operator.MatchesExact)
{
terms.Add(new HighlightTerm(termValueLower, true));
}
else if (term.Operator == Operator.Matches)
{
// Split the term value
RangeSet set = splitter.Split(termValueLower);
// Add each range as a word to the result [exact when under expand length limit]
for (int i = 0; i < set.Count; ++i)
{
Range r = set.Ranges[i];
ByteBlock partBlock = new ByteBlock(termValueLower.Array, r.Index, r.Length);
terms.Add(new HighlightTerm(partBlock, partBlock.Length < WordIndex.MinimumPrefixExpandLength));
}
}
}
}
return(terms);
}