More arcgisscripting hacking

As I mentioned in an earlier post, I've been fumbling around trying to learn how to get a python program that can talk to ARCGis. After getting around some initial irritations, I'm actually making some headway. I found this series of posts particularly helpful. As a reminder to myself, and as help for anyone else grappling with this, I'll post the first non-trivial script I've come up with here. This script is still pretty simple -- it opens up a shapefile and reads all the information associated with the shapefile. Here it is:



import arcgisscripting
import sys

#This is my first attempt to do some python
#scripting with ArcGIS Geocomputation object

#first we create the gis scripting object
gp = arcgisscripting.create(9.3)

gp.Workspace = "C:/tmp"
#allow old files to be overwritten
gp.OverWriteOutput = True

#lets print out some information about a layer
shapefile= "C:/tmp/test.shp"
desc = gp.Describe(shapefile)

#From Describe object
print desc.DataType
print desc.CatalogPath

#From FeatureClass object. The Describe object
#that is returned by the above call to Describe
#is also a 'FeatureClass' object. I havent quite
#got my head around the data model used by the
#geoprocessing object, so I don't quite understand
#how we know which fields are available and which
#arent after a call to describe.... but these work
#for the shape file I'm using.
print desc.ShapeType
print desc.FeatureType
print desc.ShapeFieldName

#list the fields. This is the same as
#returned by ListFields()
for f in desc.Fields:
....print " "+f.Name


#now go and read each line in the spatial
#data table associated with the shapefile.

#first we get a 'read' cursor
readCursor = gp.SearchCursor(shapefile)

#make sure we are at the start
readCursor.Reset()

#now go through and read (and print out) each row
row = readCursor.Next()
while (row != None):
....#print the contents of the row
....resstr = "ROW: "
....for f in desc.Fields:
........resstr = resstr + str(row.GetValue(f.Name)) + " , "
....print resstr

row = readCursor.Next()


#done!