ArcGIS Pro 2.7 API Reference Guide
IsProjected Property (SpatialReference)
Example 

ArcGIS.Core.Geometry Namespace > SpatialReference Class : IsProjected Property
Gets if this is a projected coordinate system.
Syntax
public bool IsProjected {get;}
Public ReadOnly Property IsProjected As Boolean
Example
SpatialReference wgs84 = SpatialReferences.WGS84;
bool isProjected = wgs84.IsProjected;     // false
bool isGeographic = wgs84.IsGeographic;   // true
Requirements

Target Platforms: Windows 10, Windows 8.1

See Also

Reference

SpatialReference Class
SpatialReference Members