Edit attribute table for shapefiles in folders and subfolders with arcpy?

Question

Continuously to Merge shapefiles in folders and subfolders with arcpy I try to edit attribute table for 20 shapefiles that spread in big a folder and are divided to a lot of sub folders. All shapefiles are called "migrashim" and the name of the filed that i want to change is "structuretype". I try this code:

import arcpy,os,sys,string,fnmatch,arcpy.mapping
from arcpy import env
rootPath = r"C:\Project\layers"
pattern = 'migrashim.shp'
features = arcpy.UpdateCursor(r"C:\Project\layers\*.shp")
counter = 0
for root, dirs, files in os.walk(rootPath):
 for filename in files:
 if filename == "migrashim.shp":
 for feature in features:
 if feature.structuretype == 3:
 feature.structuretype = 4
 features.updateRow(feature)
 counter = counter + 1
print 'edit'
print counter
del feature,features

but i got an error:

IOError: "C:\Project\layers\migrashim.shp" does not exist

What wrong with my code?

• PolyGeo: I recommend investigating arcpy.mapping (in particular ListLayers) and arcpy.da.Walk both here and in the ArcGIS Help.
• Emil Brundage: Which version of ArcGIS are you using?
• newGIS: I'm using arcview 10.3

Answer 1

I would use below code--

If you have access to "Data Access Module"

import arcpy,os,sys
pattern = 'fish_46.shp'
folder = 'C:\Users\USER_NAME\Desktop\delete'## root folder
field = 'Id' ## your field where calculation to be applied
files_process = []
for root,dirs,files in os.walk('C:\Users\USER_NAME\Desktop\delete'):
 for filenames in files:
 if filenames == pattern:
 files_process.append(os.path.join(root, filenames))
for i in files_process:
 curU = arcpy.da.UpdateCursor(i,field)
 for row in curU:
 row[0]=1 ##Any expression you want
 curU.updateRow(row)
del curU

EDIT

If you do not have access to "Data Access Module"

import arcpy,os,sys
pattern = 'fish_46.shp'
folder = 'C:\Users\USER_NAME\Desktop\delete'## root folder
field = 'Id' ## your field where calculation to be applied
files_process = []
for root,dirs,files in os.walk('C:\Users\USER_NAME\Desktop\delete'):
 for filenames in files:
 if filenames == pattern:
 files_process.append(os.path.join(root, filenames))
for i in files_process:
 curU = arcpy.UpdateCursor(i)
 for row in curU:
 row.setValue(field, 500)##Any expression you want
 curU.updateRow(row)
del curU

• newGIS: i get an error: UnicodeDecodeError: 'utf8' codec can't decode byte 0xe2 in position 18: invalid continuation byte
• Learner: I checked the code right now and it's working perfectly.Please confirm there is no non-ASCII chars in the scope this script gets through and please do not cut-copy-paste code into the IDE from ms-word, notepad etc. I found some times those text processors convert simple inverted commas into bizarre non-unicode/ascii chars and again i am to type them manually.
• newGIS: i get an error: File "C:\Program Files (x86)\ArcGIS\Desktop10.3\ArcPy\arcpy\arcobjects\mixins.py", line 16, in <module> curU = arcpy.da.UpdateCursor(i,field) AttributeError: 'module' object has no attribute 'da' i need help please
• Learner: Please try latter code..
• Learner: Use the later added, i mean second block, i mean lowest code after the word EDIT in my answer....................