ArcGIS Pro 3.4 API Reference Guide
ArcGIS.Core.CIM Namespace / MaplexLinePlacementMethod Enumeration
Example Example Version

MaplexLinePlacementMethod Enumeration
Maplex line placement methods.
Syntax
Members
MemberDescription
CenteredCurvedOnLine Centered curved on the line.
CenteredHorizontalOnLine Centered horizontal on the line.
CenteredPerpendicularOnLine Centered perpendicular on the line.
CenteredStraightOnLine Centered straight on the line.
OffsetCurvedFromLine Offset and curved from the line.
OffsetHorizontalFromLine Offset and horizontal from the line.
OffsetPerpendicularFromLine Offset perpendicular from the line.
OffsetStraightFromLine Offset and straight from the line.
Example
Modify the Placement/Position of labels - Line geometry
//Note: call within QueuedTask.Run()

//Get the layer's definition
var lyrDefn = featureLayer.GetDefinition() as CIMFeatureLayer;
//Get the label classes - we need the first one
var listLabelClasses = lyrDefn.LabelClasses.ToList();
var theLabelClass = listLabelClasses.FirstOrDefault();
//Modify label Placement 
//Check if the label engine is Maplex or standard.
CIMGeneralPlacementProperties labelEngine = 
    MapView.Active.Map.GetDefinition().GeneralPlacementProperties;
if (labelEngine is CIMStandardGeneralPlacementProperties)
{
  //Current labeling engine is Standard labeling engine
  var lineLablePosition = new CIMStandardLineLabelPosition
  {
    Perpendicular = true,
    Parallel = false,
    ProduceCurvedLabels = false,
    Horizontal = false,
    OnTop = true
  };
  theLabelClass.StandardLabelPlacementProperties.LineLabelPosition = 
      lineLablePosition;
}
else //Current labeling engine is Maplex labeling engine
{
  theLabelClass.MaplexLabelPlacementProperties.LinePlacementMethod = 
                MaplexLinePlacementMethod.CenteredPerpendicularOnLine;
  theLabelClass.MaplexLabelPlacementProperties.LineFeatureType = 
                MaplexLineFeatureType.General;
}
//theLabelClass.MaplexLabelPlacementProperties.LinePlacementMethod = MaplexLinePlacementMethod.CenteredPerpendicularOnLine;
lyrDefn.LabelClasses = listLabelClasses.ToArray(); //Set the labelClasses back
featureLayer.SetDefinition(lyrDefn); //set the layer's definition
Inheritance Hierarchy

System.Object
   System.ValueType
      System.Enum
         ArcGIS.Core.CIM.MaplexLinePlacementMethod

Requirements

Target Platforms: Windows 11, Windows 10

ArcGIS Pro version: 3 or higher.
See Also