List <LineSegment> RemoveInternal(int offset, int length)
{
Debug.Assert(length >= 0);
if (length == 0)
{
return(null);
}
LineSegmentTree.Enumerator it = lineCollection.GetEnumeratorForOffset(offset);
LineSegment startSegment = it.Current;
int startSegmentOffset = startSegment.Offset;
if (offset + length < startSegmentOffset + startSegment.TotalLength)
{
// just removing a part of this line segment
startSegment.RemovedLinePart(offset - startSegmentOffset, length);
SetSegmentLength(startSegment, startSegment.TotalLength - length);
return(null);
}
// merge startSegment with another line segment because startSegment's delimiter was deleted
// possibly remove lines in between if multiple delimiters were deleted
int charactersRemovedInStartLine = startSegmentOffset + startSegment.TotalLength - offset;
Debug.Assert(charactersRemovedInStartLine > 0);
startSegment.RemovedLinePart(offset - startSegmentOffset, charactersRemovedInStartLine);
LineSegment endSegment = lineCollection.GetByOffset(offset + length);
if (endSegment == startSegment)
{
// special case: we are removing a part of the last line up to the
// end of the document
SetSegmentLength(startSegment, startSegment.TotalLength - length);
return(null);
}
int endSegmentOffset = endSegment.Offset;
int charactersLeftInEndLine = endSegmentOffset + endSegment.TotalLength - (offset + length);
endSegment.RemovedLinePart(0, endSegment.TotalLength - charactersLeftInEndLine);
startSegment.MergedWith(endSegment, offset - startSegmentOffset);
SetSegmentLength(startSegment, startSegment.TotalLength - charactersRemovedInStartLine + charactersLeftInEndLine);
startSegment.DelimiterLength = endSegment.DelimiterLength;
// remove all segments between startSegment (excl.) and endSegment (incl.)
it.MoveNext();
List <LineSegment> removedLines = new List <LineSegment>();
LineSegment segmentToRemove;
do
{
segmentToRemove = it.Current;
it.MoveNext();
lineCollection.RemoveSegment(segmentToRemove);
removedLines.Add(segmentToRemove);
segmentToRemove.Deleted();
} while (segmentToRemove != endSegment);
return(removedLines);
}
private void RemoveInternal(ref DeferredEventList deferredEventList, int offset, int length)
{
LineSegment current;
if (length == 0)
{
return;
}
LineSegmentTree.Enumerator enumeratorForOffset = this.lineCollection.GetEnumeratorForOffset(offset);
LineSegment delimiterLength = enumeratorForOffset.Current;
int num = delimiterLength.Offset;
if (offset + length < num + delimiterLength.TotalLength)
{
delimiterLength.RemovedLinePart(ref deferredEventList, offset - num, length);
this.SetSegmentLength(delimiterLength, delimiterLength.TotalLength - length);
return;
}
int totalLength = num + delimiterLength.TotalLength - offset;
delimiterLength.RemovedLinePart(ref deferredEventList, offset - num, totalLength);
LineSegment byOffset = this.lineCollection.GetByOffset(offset + length);
if (byOffset == delimiterLength)
{
this.SetSegmentLength(delimiterLength, delimiterLength.TotalLength - length);
return;
}
int num1 = byOffset.Offset;
int totalLength1 = num1 + byOffset.TotalLength - (offset + length);
byOffset.RemovedLinePart(ref deferredEventList, 0, byOffset.TotalLength - totalLength1);
delimiterLength.MergedWith(byOffset, offset - num);
this.SetSegmentLength(delimiterLength, delimiterLength.TotalLength - totalLength + totalLength1);
delimiterLength.DelimiterLength = byOffset.DelimiterLength;
enumeratorForOffset.MoveNext();
do
{
current = enumeratorForOffset.Current;
enumeratorForOffset.MoveNext();
this.lineCollection.RemoveSegment(current);
current.Deleted(ref deferredEventList);
}while (current != byOffset);
}