AttributeError: __exit__

[VishalShah2]

Hello,

So I am new to working with cursors and need a little help with my code as I am getting an AttributeError: __exit__ when i run my script. Here's what my code looks like:

inTable = r'Layer\Fiber'
routeMilesField = "RouteMiles"
strandsField = "cableSize"
milesField = "FiberMiles"
fields = [strandsField, milesField, routeMilesField]


with arcpy.UpdateCursor(fiberFeatures, fields) as cursor:
    for row in cursor:
        if None in row[:-1]:
            arcpy.AddMessage("Insufficient Strand Data!")
            break
        else:
            row[2] = row[0] * row[1]
            cursor.updateRow(row)‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Any help is greatly appreciated!

Edit:

Revised script based on this article: cursor - AttributeError: __exit__ when trying to use arcpy.UpdateCursor - Geographic Information Sys... 

cursor = arcpy.UpdateCursor(fiberFeatures, fields)
for row in cursor:
    if None in row[:-1]:
        arcpy.AddMessage("Insufficient Strand Data")
        break
    else:
        row[2] = row[0] * row[1]
        cursor.updateRow(row)‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

This returns a TypeError: 'Row' object has no attribute '__getitem__' error. I'm new to cursors and what not and definitely need help with this code.

Edit 2: Solution based on Joshua's feedback:

with arcpy.da.UpdateCursor(fiberFeatures, fields) as cursor:
    for row in cursor:
        if None in row[:-1]:
            arcpy.AddError("Insufficient Strand Data!")
            break
        else:
            row[2] = row[0] * row[1]
            cursor.updateRow(row)‍‍‍‍‍‍‍‍

[RebeccaStrauch__GISP]

You are missing a quote at the end of the first line.  See if that makes a difference

inTable = r'Layer\Fiber'

[VishalShah2]

Apologies Rebecca, my code actually has the quote at the end. I forgot to type that in. But that doesn't seem to cause the error. Any other ideas?

[RebeccaStrauch__GISP]

Ah yes, typos happen.  I saw the missing quote and didn't go beyond that since need to fix the obvious errors first.   Looks like you have it resolved now.

[VishalShah2]

Thank you for the help! It was greatly appreciated!

[DanPatterson_Retired]

it is hard to provide an example without creating a class or running a file, but have you considered reversing your condition or do you want to completely bail?

if not(None in row[:-1]):
    row[2] = row[0] * row[1]
    cursor.updateRow(row)‍‍‍

[VishalShah2]

I am open to anything Dan as long as it does what I need it to do. The path I am taking is to sort through the strandsField to first see if there are any NULL values, if there are any, return a message saying Insufficient Data. If there are no NULL values, then multiple the strandsField with the milesField. But I want the first conditional to run to inform users if there is insufficient data. Hopefully that makes sense!

[VishalShah2]

Dan, I just tried it with the code you had listed but within the with statement:

with arcpy.UpdateCursor(fiberFeatures, fields) as cursor:
    if not(None in row[:-1]):
        row[2] = row[0] * row[1]
        cursor.updateRow(row)‍‍‍‍

This still gives me the AttributeError: __Exit__

[JoshuaBixby · Accepted solution]

Instead of investing in fixing code that uses the old ArcPy cursors, I recommend spending a few minutes to read up on the not-so-new ArcPy Data Access cursors.  They are much more efficient, and a bit more Pythonic, than the original Python cursors.  UpdateCursor—Help | ArcGIS Desktop 

[VishalShah2]

That did the trick Joshua. Changing it from arcpy.UpdateCursor to arcpy.da.UpdateCursor.