LayoutFarm.Text.InternalTextLayerController.AddCharToCurrentLine C# (CSharp) Method

        public void AddCharToCurrentLine(char c)
        {
            updateJustCurrentLine = true;
            bool passRemoveSelectedText = false;
#if DEBUG
            if (dbugEnableTextManRecorder)
            {
                dbugTextManRecorder.WriteInfo("TxLMan::AddCharToCurrentLine " + c);
                dbugTextManRecorder.BeginContext();
            }
#endif
            if (SelectionRange != null)
            {
#if DEBUG
                if (dbugEnableTextManRecorder)
                {
                    dbugTextManRecorder.WriteInfo(SelectionRange);
                }
#endif
                RemoveSelectedText();
                passRemoveSelectedText = true;
            }
            if (passRemoveSelectedText && c == ' ')
            {
            }
            else
            {
                commandHistory.AddDocAction(
                  new DocActionCharTyping(c, textLineWriter.LineNumber, textLineWriter.CharIndex));
            }

            textLineWriter.AddCharacter(c);
#if DEBUG
            if (dbugEnableTextManRecorder)
            {
                dbugTextManRecorder.EndContext();
            }
#endif
        }
        public EditableRun CurrentTextRun

        public void OnKeyPress(UIKeyEventArgs e)
        {
            this.SetCaretState(true);
            //------------------------
            if (e.IsControlCharacter)
            {
                OnKeyDown(e);
                return;
            }

            char c = e.KeyChar;

            e.CancelBubbling = true;
            if (internalTextLayerController.SelectionRange != null &&
                internalTextLayerController.SelectionRange.IsValid)
            {
                InvalidateGraphicLocalArea(this, GetSelectionUpdateArea());
            }
            bool preventDefault = false;

            if (textSurfaceEventListener != null &&
                !(preventDefault = TextSurfaceEventListener.NotifyPreviewKeydown(textSurfaceEventListener, c)))
            {
                internalTextLayerController.UpdateSelectionRange();
            }
            if (preventDefault)
            {
                return;
            }
            if (internalTextLayerController.SelectionRange != null)
            {
                internalTextLayerController.AddCharToCurrentLine(c);
                if (textSurfaceEventListener != null)
                {
                    TextSurfaceEventListener.NotifyCharactersReplaced(textSurfaceEventListener, e.KeyChar);
                }
            }
            else
            {
                internalTextLayerController.AddCharToCurrentLine(c);
                if (textSurfaceEventListener != null)
                {
                    TextSurfaceEventListener.NotifyCharacterAdded(textSurfaceEventListener, e.KeyChar);
                }
            }

            EnsureCaretVisible();
            if (textSurfaceEventListener != null)
            {
                TextSurfaceEventListener.NotifyKeyDown(textSurfaceEventListener, e.KeyCode);
            }
        }