/// <summary>
/// Moves the caret to the next valid CaretPosition
/// </summary>
/// <returns>An CaretPosition containing the valid values of the caret after the move has occurred.</returns>
/// <remarks>This method will take care of surrogate pairs and combining character sequences.</remarks>
public CaretPosition MoveToNextCaretPosition()
{
CaretPosition oldPosition = this.Position;
ITextViewLine line = _wpfTextView.GetTextViewLineContainingBufferPosition(oldPosition.BufferPosition);
if (oldPosition.BufferPosition == line.End && line.IsLastTextViewLineForSnapshotLine)
{
//At the physical end of a line, either increase virtual space or move to the start of the next line.
if (this.IsVirtualSpaceOrBoxSelectionEnabled)
{
//Increase virtual spaces by one.
return(this.MoveTo(new VirtualSnapshotPoint(line.End, oldPosition.VirtualSpaces + 1)));
}
else if (oldPosition.BufferPosition == _wpfTextView.TextSnapshot.Length)
{
return(oldPosition);
}
else
{
//Move to the start of the next line (the position at the end of the line break is also the start of the next line).
return(this.MoveTo(line.EndIncludingLineBreak, PositionAffinity.Successor, true));
}
}
else
{
//Not at the end of a line ... just move to the end of the current text element.
SnapshotSpan textElementSpan = _wpfTextView.GetTextElementSpan(oldPosition.BufferPosition);
return(this.MoveTo(textElementSpan.End, PositionAffinity.Successor, true));
}
}
private void EnsureVirtualSelectedSpans()
{
if (_virtualSelectedSpans == null)
{
_virtualSelectedSpans = new List <VirtualSnapshotSpan>();
if (this.IsEmpty)
{
VirtualSnapshotPoint caretPoint = this.ActivePoint; //== this.AnchorPoint
_virtualSelectedSpans.Add(new VirtualSnapshotSpan(caretPoint, caretPoint));
}
else
{
if (this.Mode == TextSelectionMode.Box)
{
SnapshotPoint current = this.Start.Position;
VirtualSnapshotPoint end = this.End;
do
{
ITextViewLine line = _wpfTextView.GetTextViewLineContainingBufferPosition(current);
VirtualSnapshotSpan?span = this.GetSelectionOnTextViewLine(line);
if (span.HasValue)
{
_virtualSelectedSpans.Add(span.Value);
}
if (line.LineBreakLength == 0 && line.IsLastTextViewLineForSnapshotLine)
{
break; //Just processed last text view line in buffer.
}
current = line.EndIncludingLineBreak;
}while ((current.Position <= end.Position.Position) || //Continue while the virtual space version of current
(end.IsInVirtualSpace && (current.Position == end.Position.Position))); //is less than the virtual space position of the end of selection.
}
else
{
_virtualSelectedSpans.Add(new VirtualSnapshotSpan(this.Start, this.End));
}
}
}
}
