var prj = DlxApp.GetJob().GetProject("Example Sch");
if (!prj.IsValid())
  prj = DlxApp.GetJob().NewProject("Example Sch");
var doc = prj.GetDocument("Examples Sch", DlxApp.DOCTYPE_SCHEMATIC);
if (!doc.IsValid())
{
  doc = prj.NewDocument("Examples Sch", DlxApp.DOCTYPE_SCHEMATIC);
  doc.SetPageFormat("A4", false);
}
if (doc.IsValid() && doc.Activate())
{
  var page = doc.GetActivePage();
  if (page.IsValid())
  {
    var layer = page.GetLayerFromType(DlxApp.LAYERTYPE_DRAWING);
    if (layer.IsValid())
    {
      var pos = layer.GetFrontObjectIterator();
      while (pos.IsValid())
      {
        var obj = layer.GetNextObject(pos);
        if (obj.GetType() == DlxApp.OBJTYPE_LINE)
        {
          // Extends the line.
          var angle = obj.GetStartPoint().ArcAngle(obj.GetEndPoint());
          obj.SetStartPoint(obj.GetStartPoint().CirclePoint(-10, angle));
          obj.SetEndPoint(obj.GetEndPoint().CirclePoint(10, angle));
          // Set the line thickness to 2mm.
          var pen = new DlxPenStyle();
          obj.GetStyle(pen);
          pen.SetWidth(2);
          obj.SetStyle(pen);
        }
      }
    }
  }
}