How to programmatically determine whether a spatial reference factory code is valid?

Question

I am using the following code segment to create a spatial reference.

 spatialReferance = arcpy.SpatialReference()
 spatialReferance.factoryCode = spatialReferanceFactoryCode
 spatialReferance.create()

But it gives the following error:

Runtime error : ERROR 999999: Error executing function. the input string is not a geographic or projected coordinate system

How can I programmatically determine whether a factory code is valid or not?

• om_henners: What is the value of spatialReferanceFactoryCode?
• Emi: @om_henners: spatialReferanceFactoryCode = 32146

Answer 1

See Do ArcGIS SpatialReference object factory codes correspond with EPSG numbers? in particular @mkennedy and @blah238 answers.

As to whether a factory code is valid or not... In Python, you can use the EAFP method (Easier to Ask for Forgiveness than Permission)

try:
 spatialReference.factoryCode = spatialReferenceFactoryCode
 spatialReference.create()
except RuntimeError:
 print 'factoryCode is not valid'

• Emi: Actually I want to check if the code valid or not. Is there any property that can tell me that?
• om_henners: @Emi Try spatialreference.org (it is by the way)
• Emi: @om_henners: sorry for the misunderstanding. Actually I want to do it programmatically.
• mkennedy: There is no way to check whether a code is valid without trying to create a coordinate system (spatial reference).
• Michael Stimson: +1 for EAFP method. That is so python! Try to do it and catch it if it breaks.. there isn't a IsNumeric for strings in python (off topic but related) possibly because you can find out in the same way.