LayoutFarm.HtmlBoxes.SelectionRange.CopyText C# (CSharp) Method

        public void CopyText(StringBuilder stbuilder)
        {
            //copy selected text to stbuilder 
            //this version just copy a plain text
            int j = selectedLines.Count;
            for (int i = 0; i < j; ++i)
            {
                var selLine = selectedLines[i];
                var selSeg = selLine.SelectionSegment;
                switch (selSeg.Kind)
                {
                    case SelectionSegmentKind.Partial:
                        {
                            var startRun = selSeg.StartHitRun;
                            var endHitRun = selSeg.EndHitRun;
                            bool autoFirstRun = false;
                            bool autoLastRun = false;
                            if (startRun == null)
                            {
                                startRun = selLine.GetFirstRun();
                                autoFirstRun = true;
                            }
                            if (endHitRun == null)
                            {
                                endHitRun = selLine.GetLastRun();
                                autoLastRun = true;
                            }

                            if (startRun == endHitRun)
                            {
                                var rr = startRun as CssTextRun;
                                if (this.startHitRunCharIndex >= 0)
                                {
                                    var alltext = rr.Text;
                                    var sub1 = alltext.Substring(this.startHitRunCharIndex, this.endHitRunCharIndex - this.startHitRunCharIndex);
                                    stbuilder.Append(sub1);
                                }
                            }
                            else
                            {
                                int runCount = selLine.RunCount;
                                for (int n = 0; n < runCount; ++n)
                                {
                                    //temp fix here!
                                    //TODO: review this for other cssrun type
                                    var rr = selLine.GetRun(n) as CssTextRun;
                                    if (rr == null)
                                    {
                                        continue;
                                    }
                                    if (rr == startRun)
                                    {
                                        var alltext = rr.Text;
                                        if (autoFirstRun)
                                        {
                                            stbuilder.Append(alltext);
                                        }
                                        else
                                        {
                                            if (this.startHitRunCharIndex >= 0)
                                            {
                                                var sub1 = alltext.Substring(this.startHitRunCharIndex);
                                                stbuilder.Append(sub1);
                                            }
                                        }
                                    }
                                    else if (rr == endHitRun)
                                    {
                                        var alltext = rr.Text;
                                        if (autoLastRun)
                                        {
                                            stbuilder.Append(alltext);
                                        }
                                        else
                                        {
                                            if (this.endHitRunCharIndex >= 0)
                                            {
                                                var sub1 = alltext.Substring(0, this.endHitRunCharIndex);
                                                stbuilder.Append(sub1);
                                            }
                                        }
                                        //stop
                                        break;
                                    }
                                    else
                                    {
                                        stbuilder.Append(rr.Text);
                                    }
                                }
                            }
                        }
                        break;
                    default:
                        {
                            int runCount = selLine.RunCount;
                            for (int n = 0; n < runCount; ++n)
                            {
                                var r = selLine.GetRun(n) as CssTextRun;
                                if (r != null)
                                {
                                    stbuilder.Append(r.Text);
                                }
                            }
                        }
                        break;
                }

                if (i < j - 1)
                {
                    //if not lastline
                    stbuilder.AppendLine();
                }
            }
        }

 public override void CopySelection(StringBuilder stbuilder)
 {
     if (_currentSelectionRange != null)
     {
         _currentSelectionRange.CopyText(stbuilder);
     }
 }