public void AddSpan(int index, int length, string lang, string style, string url)
{
var span = new FormatSpan {
Index = index, Length = length, Lang = lang, Class = style, LinkURL = url
};
_spans.Add(span);
}
private static void AdjustSpan(FormatSpan span, int location, int length)
{
if (span.Length <= 0)
{
return; // we've already deleted all the characters in the span.
}
if (location > span.Index + span.Length || length == 0)
{
return; // the change doesn't affect the span.
}
// Adding characters to the end of the span is probably desireable if they differ.
if (length > 0)
{
// Inserting characters is fairly easy to deal with.
if (location <= span.Index)
{
span.Index += length;
}
else
{
span.Length += length;
}
}
// The span changes only if the deletion starts before the end of the span.
else if (location < span.Index + span.Length)
{
// Deleting characters has a number of cases to deal with.
// Remember, length is a negative number here!
if (location < span.Index)
{
if (span.Index + length >= location)
{
span.Index += length;
}
else
{
int before = span.Index - location;
span.Index = location;
span.Length += (before + length);
}
}
else
{
span.Length += length;
if (span.Length < location - span.Index)
{
span.Length = location - span.Index;
}
}
}
}
private static FormatSpan?HighlightSpan(FormatSpan currentHighlight, List <Cell> cells, int cellIndex, int endPosition)
{
var highlightedFullWidthOffset = 0;
int i;
for (i = cellIndex; i < Math.Min(endPosition + currentHighlight.Length + highlightedFullWidthOffset, cells.Count); i++)
{
highlightedFullWidthOffset += cells[i].ElementWidth - 1;
cells[i].Formatting = currentHighlight.Formatting;
}
if (i != cells.Count)
{
return(null);
}
return(currentHighlight);
}
