var count = 0;
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)
        {
          count++;
        }
      }
    }
  }
}
DlxApp.Printf("The drawing contains %i lines.", count);