Get the LabelSetId from Alignment class

Table of Contents

Motivation
The workaround – extension method

Motivation #

Civil 3D offers API to create an Alignment via the Alignment.Create static method. Interestingly, even though it takes in a LabelSetId as a constructor parameter, but it doesn’t expose the parameter. Which is really unfortunate.

The workaround – extension method #

So we need to write our own extension method for it. Based on Norman Yuan’s idea on a forum post, here’s the implementation.

  public static AlignmentLabelSetStyle GetLabelSet(this Alignment alignment,
      CivilDocument civilDoc, Transaction ts)
  {

      foreach (ObjectId labelGroupId in alignment.GetAlignmentLabelGroupIds())
      {
          var labelGroup = ts.GetObject<AlignmentLabelGroup>(labelGroupId);
          foreach (var alignmentLabelSetStyleId in civilDoc.Styles.LabelSetStyles.AlignmentLabelSetStyles)
          {
              var alignmentLabelSetStyle = ts.GetObject<AlignmentLabelSetStyle>(alignmentLabelSetStyleId);
              foreach (var labelSetItem in alignmentLabelSetStyle)
              {
                  if (labelSetItem.LabelStyleName == labelGroup.StyleName
                      && SameLabelType(labelSetItem.LabelStyleType, labelGroup.LabelType))
                  {
                      return alignmentLabelSetStyle;
                  }
              }

          }

      }

      return null;
  }

 //this is unfortunate but I haven't find a more elegant way to map the two different LabelType
  private static bool SameLabelType(LabelStyleType labelStyleType, LabelType labelType)
  {
      switch (labelType) 
      {
          case LabelType.SurfaceContour:
              return labelStyleType == LabelStyleType.SurfaceContour;
          case LabelType.AlignmentMajorStation:
              return labelStyleType == LabelStyleType.AlignmentMajorStation;
          case LabelType.AlignmentMinorStation:
              return labelStyleType == LabelStyleType.AlignmentMinorStation;
          case LabelType.AlignmentGeometryPoint:
              return labelStyleType == LabelStyleType.AlignmentGeometryPoint;
          case LabelType.AlignmentProfileGeometryPoint:
              return labelStyleType == LabelStyleType.AlignmentProfileGeometryPoint;
          case LabelType.AlignmentStationEquation:
              return labelStyleType == LabelStyleType.AlignmentStationEquation;
          case LabelType.AlignmentDesignSpeed:
              return labelStyleType == LabelStyleType.AlignmentDesignSpeed;
          case LabelType.AlignmentSuperelevationCriticalPoints:
              return labelStyleType == LabelStyleType.AlignmentSuperelevationCriticalPoints;
          case LabelType.AlignmentStationOffset:
              return labelStyleType == LabelStyleType.AlignmentStationOffset;
          case LabelType.AlignmentCurve:
              return labelStyleType == LabelStyleType.AlignmentCurve;
          case LabelType.AlignmentSpiral:
              return labelStyleType == LabelStyleType.AlignmentSpiral;
          case LabelType.AlignmentTangentIntersection:
              return labelStyleType == LabelStyleType.AlignmentTangentIntersection;
          case LabelType.AlignmentPointOfIntersection:
              return labelStyleType == LabelStyleType.AlignmentPointOfIntersection;
          case LabelType.ProfileMajorStation:
              return labelStyleType == LabelStyleType.ProfileMajorStation;
          case LabelType.ProfileMinorStation:
              return labelStyleType == LabelStyleType.ProfileMinorStation;
          case LabelType.ProfileHorizontalGeometryPoint:
              return labelStyleType == LabelStyleType.ProfileHorizontalGeometryPoint;
          case LabelType.ProfileGradeBreaks:
              return labelStyleType == LabelStyleType.ProfileGradeBreaks;
          case LabelType.ProfileLine:
              return labelStyleType == LabelStyleType.ProfileLine;
          case LabelType.ProfileCrestCurve:
              return labelStyleType == LabelStyleType.ProfileCrestCurve;
          case LabelType.ProfileSagCurve:
              return labelStyleType == LabelStyleType.ProfileSagCurve;
          case LabelType.ProfileViewDepth:
              return labelStyleType == LabelStyleType.ProfileViewDepth;
          case LabelType.SectionViewOffsetElevation:
              return labelStyleType == LabelStyleType.SectionViewOffsetElevation;
          case LabelType.SectionMajorOffset:
              return labelStyleType == LabelStyleType.SectionMajorOffset;
          case LabelType.SectionMinorOffset:
              return labelStyleType == LabelStyleType.SectionMinorOffset;
          case LabelType.SectionGradeBreak:
              return labelStyleType == LabelStyleType.SectionGradeBreak;
          case LabelType.SectionSegment:
              return labelStyleType == LabelStyleType.SectionSegment;
          case LabelType.ViewFrame:
              return labelStyleType == LabelStyleType.ViewFrame;
          case LabelType.SectionCorridorPoint:
              return labelStyleType == LabelStyleType.SectionCorridorPoint;
          default:
              return false;
      }
  }

You can just call alignment.GetLabelSet(civilDoc, ts).ObjectId to get the ObjectId for the LabelSetId.