ArcGIS Pro 2.6 API Reference Guide
Length3D Property (Envelope)

ArcGIS.Core.Geometry Namespace > Envelope Class : Length3D Property
Gets the 3D length of the perimeter of this instance.
Syntax
public double Length3D {get;}
Public ReadOnly Property Length3D As Double
Exceptions
ExceptionDescription
The geometry is not z-aware.
Requirements

Target Platforms: Windows 10, Windows 8.1, Windows 7

See Also

Reference

Envelope Class
Envelope Members