Creating Toolboxes and Scripts

Start by opening or creating a new map document in ArcMap

To create a new Toolbox for your ArcPy scripts,

Click the Toolbox icon

When the Toolbox opens up, right-click �and select Add Toolbox�

To create a new toolbox, Click in the upper right of the Add Toolbox dialog. A new entry shows up in the list (e.g. Toolbox.tbx). Rename it to whatever you want (I use MyToolbox.tbx) making sure to keep the .tbx extension.

Select your new toolbox in the Add Toolbox dialog and click Open. Your toolbox now appears in the list for the ArcToolbox window. I would advise you to save your map document at this point so that your toolbox always shows up in the ArcToolbox window every time you open it.

To add a script to your toolbox,

Right-click your toolbox (e.g. MyToolbox) in the ArcToolbox window and select Add�Script�

Fill in the fields in the Add Script dialog. For Name, add a descriptive name that has no spaces or underscore characters in it (who knows why�) The text in the Name field does not have to be identical to the name of your script but for the sake of clarity it�s a good idea to keep them somewhat similar. For Label, add a descriptive name that will identify your script under your toolbox. Enter a Description of what the tool does (no restrictions on text in here). Here�s how mine looks for a simple, �hello world� script:

Click Next. Click the browse button �and you will be prompted to enter the path for a script file. You can enter the path to an existing file or you can create a new empty file. Here I�ll give you instructions to create a new, empty script. Navigate to a folder that has (or will have) script files in it. All ArcPy scripts have a .py extension. To create a new file, just enter the desired file in the Script File text field. Here�s mine:

Click Open and the path to your script will appear in the Add Script window:

Click Next. If you entered the name of a new file, you will see this window:

Click Yes. You will be prompted to add parameters:

When executed, a script with parameters will launch an interactive dialog box. Our new script will not have any parameters so just click Finish. Your script will now appear in the ArcToolbox window under your toolbox. Here�s mine:

Adding content to your script

Right now, our script is an empty text file. Right click your script in ArcToolbox and select Edit� Your system text editor will pop up (usually a version of Notepad on Windows). Please note: don�t edit in Word or any other word processor! They use characters outside of the set that Python recognizes�your code will not run!

In Notepad, add the following lines to your script:

import arcpy������ # the module that links to the ArcGIS universe of code

arcpy.AddMessage('hello out there!')� # prints an inspirational message to the console

Save your file.

Back in ArcMap, double click your script in ArcToolbox. A window representing your script pops up. Here�s mine:

Click OK. Now a console window pops up with your script�s output:

You can click Close when you have finished admiring your work. Congratulations!

Be sure to save your map document!

Things that typically go wrong

Make sure your scripts end with a .py extension

Case counts in Python! If you import ArcPy instead of arcpy, you get this friendly message in the console window:

Failure!!! So dramatic!

Obviously, all kinds of things will go wrong but we�ll figure out how to fix them. Don�t panic.

Something to try on the ArcPy command line

Open the Python window by clicking on the button bar

Then enter this code:

>>> import arcpy

>>> mxd = arcpy.mapping.MapDocument("CURRENT")

>>> mxd.author = "Rebop Kwaku Baah (or your name)"

Finally, select File�Map Document Properties and look for your handiwork�