ArcGIS Pro 2.6 API Reference Guide
Intersection Method (Envelope)
Example 

ArcGIS.Core.Geometry Namespace > Envelope Class : Intersection Method
Envelope to intersect with.
Calculates the intersection between this instance and the specified envelope.
Syntax
public Envelope Intersection( 
   Envelope envelope
)
Public Function Intersection( _
   ByVal envelope As Envelope _
) As Envelope

Parameters

envelope
Envelope to intersect with.

Return Value

The intersecting envelope or null if they don't intersect.
Remarks

Intersection

Example
Envelope env1 = EnvelopeBuilder.CreateEnvelope(0, 0, 1, 1, SpatialReferences.WGS84);
Envelope env2 = EnvelopeBuilder.CreateEnvelope(0.5, 0.5, 1.5, 1.5, SpatialReferences.WGS84);

Envelope env3 = env1.Intersection(env2);
bool intersects = env1.Intersects(env2); // true
Requirements

Target Platforms: Windows 10, Windows 8.1, Windows 7

See Also

Reference

Envelope Class
Envelope Members
Intersects Method