arcpy - Calculating geometry for feature class with x/y and Lat/Long values in different projections?

I have a feature class with x/y values populated on the native projection of the feature class (state plane).

In the same feature class I also have Lat/Long fields that I need to populate (WGS 84 in decimal degree).

The problem I have is the calculate geometry function doesn't allow me to choose a different projection other than State Plane when I try to auto populate the Lat/Long values.

Does anyone have any python code or ideas that might help with this request?

Answer

you just need to run a cursor on it and use the projectAs() geometry method.

import arcpy

fc = r'C:\path_to\your_data\points.shp'

wgs = arcpy.SpatialReference(4326)
with arcpy.da.UpdateCursor(fc, ['SHAPE@', 'lat_field', 'long_field']) as rows:
    for row in rows:

        pnt_wgs = row[0].projectAs(wgs)
        row[1:] = [pnt_wgs.centroid.Y, pnt_wgs.centroid.X] #will be in decimal degrees
        rows.updateRow(row)