ArcObjects Library Reference (Carto)  

esriMaplexRotationAlignmentType Constants

Label alignment value options.

Constant Value Description
esriMaplexRotationAlignmentStraight 0 Label is aligned straight with the rotation angle.
esriMaplexRotationAlignmentHorizontal 1 Label is kept horizontal regardless of rotation angle.
esriMaplexRotationAlignmentPerpendicular 2 Label is aligned prependicular to the rotation angle.

Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.