/// <summary> /// Validates the visual column of the caret using the specified visual line. /// The visual line must contain the caret offset. /// </summary> void RevalidateVisualColumn(VisualLine visualLine) { if (visualLine == null) throw new ArgumentNullException("visualLine"); // mark column as validated visualColumnValid = true; int caretOffset = textView.Document.GetOffset(position.Location); int firstDocumentLineOffset = visualLine.FirstDocumentLine.Offset; position.VisualColumn = visualLine.ValidateVisualColumn(position, textArea.Selection.EnableVirtualSpace); // search possible caret positions int newVisualColumnForwards = visualLine.GetNextCaretPosition(position.VisualColumn - 1, LogicalDirection.Forward, CaretPositioningMode.Normal, textArea.Selection.EnableVirtualSpace); // If position.VisualColumn was valid, we're done with validation. if (newVisualColumnForwards != position.VisualColumn) { // also search backwards so that we can pick the better match int newVisualColumnBackwards = visualLine.GetNextCaretPosition(position.VisualColumn + 1, LogicalDirection.Backward, CaretPositioningMode.Normal, textArea.Selection.EnableVirtualSpace); if (newVisualColumnForwards < 0 && newVisualColumnBackwards < 0) throw ThrowUtil.NoValidCaretPosition(); // determine offsets for new visual column positions int newOffsetForwards; if (newVisualColumnForwards >= 0) newOffsetForwards = visualLine.GetRelativeOffset(newVisualColumnForwards) + firstDocumentLineOffset; else newOffsetForwards = -1; int newOffsetBackwards; if (newVisualColumnBackwards >= 0) newOffsetBackwards = visualLine.GetRelativeOffset(newVisualColumnBackwards) + firstDocumentLineOffset; else newOffsetBackwards = -1; int newVisualColumn, newOffset; // if there's only one valid position, use it if (newVisualColumnForwards < 0) { newVisualColumn = newVisualColumnBackwards; newOffset = newOffsetBackwards; } else if (newVisualColumnBackwards < 0) { newVisualColumn = newVisualColumnForwards; newOffset = newOffsetForwards; } else { // two valid positions: find the better match if (Math.Abs(newOffsetBackwards - caretOffset) < Math.Abs(newOffsetForwards - caretOffset)) { // backwards is better newVisualColumn = newVisualColumnBackwards; newOffset = newOffsetBackwards; } else { // forwards is better newVisualColumn = newVisualColumnForwards; newOffset = newOffsetForwards; } } this.Position = new TextViewPosition(textView.Document.GetLocation(newOffset), newVisualColumn); } }