AddMessage question

[AmyKlug]

How would you do this using AddMessage instead of print and in a script tool? My code has a parameter and where_clause in the search cursor so the user inputs a name and I would like a message listing field values.

ESRI expample:

import arcpy # Open a searchcursor #  Input: C:/Data/Counties.shp #  Fields: NAME; STATE_NAME; POP2000 #  Sort fields: STATE_NAME A; POP2000 D rows = arcpy.SearchCursor("c:/data/counties.shp",                           fields="NAME; STATE_NAME; POP2000",                           sort_fields="STATE_NAME A; POP2000 D")  # Iterate through the rows in the cursor and print out the # state name, county and population of each. for row in rows:     print("State: {0}, County: {1}, Population: {2}".format(         row.getValue("STATE_NAME"),         row.getValue("NAME"),         row.getValue("POP2000")))

[T__WayneWhitley]

Are you showing the dialog box window messages?  There's a checkbox you can check on or off to show the messages...that's where they print to so I suspect you're simply not displaying it.  ...also do you know where to look at the Results panel?  You may optionally look at messages for each run and see any you have printed (along with error messages, if any, etc).

[AmyKlug]

I've been viewing message in the results window..................when the message shows up. When I indent arcpy.AddMessage under "for row in rows" it just lets me know that the tool completed. No message

[T__WayneWhitley]

Do you know you just said 'arcpy.GetMessage'... that is totally different!

[AmyKlug]

Sorry...type o. fixed

[T__WayneWhitley]

Have you set up the tool to accept your input parameter for the query you are trying to apply?

...ahh, I see a problem with your query:
"LINE_ID = 'LID'"

LID is supposed to be a variable, not the text 'LID', understand?

[T__WayneWhitley · Accepted solution]

This is kind of an important detail, easy to overlook, so I'm posting once more to clarify (hopefully).

Since this was a file gdb (as hard-coded in the script) and using GetParameterAsText for the var LID to 'filter' the search cursor, this query should work:

rows = arcpy.SearchCursor("C:/Python/Python.gdb/Counties", "LINE_ID = '" + LID + "'")


There's more than 1 way to enter a query, but basically from the webhelp topic, Specifying a Query in Python (http://resources.arcgis.com/en/help/main/10.1/index.html#//002z0000001r000000), a better recommended approach is something like:

qry = """%s = '%s'""" % (arcpy.AddFieldDelimiters(fc, "LINE_ID"), LID)
rows = arcpy.SearchCursor("C:/Python/Python.gdb/Counties", qry)

Hope that at least sums up better this rather lengthy thread --- for those still unsure what was happening, the incorrect query ("LINE_ID = 'LID'") was returning an empty set hence no messages...nothing to print.

Enjoy,
Wayne

[AmyKlug]

Worked like a charm. Muchas Gracias. Looks like I need to learn more about queries!