LayoutFarm.Text.EditableTextLine.GetPrevTextRun C# (CSharp) Method

        EditableRun GetPrevTextRun(EditableRun run)
        {
            if (IsSingleLine)
            {
                return run.PrevTextRun;
            }
            else
            {
                if (IsFirstLine)
                {
                    return run.PrevTextRun;
                }
                else
                {
                    EditableRun prevTextRun = run.PrevTextRun;
                    if (prevTextRun.IsLineBreak)
                    {
                        return null;
                    }
                    else
                    {
                        return prevTextRun;
                    }
                }
            }
        }
        EditableRun GetNextTextRun(EditableRun run)