(Required if you do not supply level 2, 3, and four address data) Contains the longitude associated with the location in degrees east. For values west of the Greenwich meridian, the longitude is a negative value.

Public Property Longitude As Nullable(Of Double)

Dim instance As GeocodeLocationOutput
Dim value As Nullable(Of Double)
 
instance.Longitude = value
 
value = instance.Longitude

public Nullable<double> Longitude {get; set;}