Automating MapPoint with Perl

This article shows how to access the MapPoint API from Perl using the Win32::OLE module. Topics include basic Perl syntax, how to call MapPoint methods, and how to set MapPoint API properties.

I've been a fan of using Perl for manipulating text files for some years having previously used AWK. Both are free, but the main advantage of using Perl is the enormous variety of modules available ranging from HTML and XML parsers, image manipulation libraries, communications and networking, mathematics libraries and so on.

One the the modules is a library for calling programs via Windows OLE. Windows applications including Microsoft Office and MapPoint can be accessed programmatically and controlled from Perl.

ActiveState provides Perl for Windows in an MSI package which is freely downloadable. After it is installed, all that is required to begin executing Perl scripts is a text file which the extension .pl containing the code. There is no "project" file or compiling that needs to occur, Perl scripts are interpreted and executed on the fly making for a very easy learning curve.

The script below defines an array with the U.S. State names, instantiates MapPoint, and loops through the array saving a map for each state. This is very similar to a previous article Automating MapPoint with the .NET SDK published on MP2K Magazine last year which basically accomplishes the same thing with the free VB .NET compiler found in the .NET SDK.

Both approaches allow you to program MapPoint for free, but in comparison automating MapPoint with Perl is much easier, not least because some de-bugging output is returned, aiding greatly in tracking down syntax errors.

Here is the script, you simply need to put this code in a text file and rename it with a .pl extension and just that simply you are able to automate MapPoint without needing an expensive development tool.

use Win32::OLE qw(in with);
use Win32::OLE::Const;
use Win32::OLE::Const 'Microsoft MapPoint';
$Win32::OLE::Warn = 3;


# die on errors...

@states = ("Alabama","Alaska","Arizona","Arkansas","California","Colorado","Connecticut",
"Delaware","Florida","Georgia","Hawaii","Idaho","Illinois","Indiana","Iowa","Kansas",
"Kentucky","Louisiana","Maine","Maryland","Massachusetts","Michigan","Minnesota",
"Mississippi","Missouri","Montana","Nebraska","Nevada","New Hampshire","New Jersey",
"New Mexico","New York","North Carolina", "North Dakota","Ohio","Oklahoma","Oregon",
"Pennsylvania","Rhode Island","South Carolina","South Dakota","Tennessee","Texas","Utah",
"Vermont","Virginia","Washington","Washington, DC","West Virginia","Wisconsin","Wyoming");

my $MapPoint = Win32::OLE->new('MapPoint.Application', 'Quit');
my $Map = $MapPoint->NewMap();

for ($i = 0; $i <= 5; $i++) {
  my $Results = $Map->FindPlaceResults($states[$i]);
  print "$states[$i]\n";
  my $Location = $Results->Item(1);
  $Location->GoTo;
  $Map->SaveAs($states[$i], 2);
}
$Map->{Saved} = -1;

The first few lines tell the Perl interpreter to include the Win32::OLE module required for communicating with MapPoint. The next section defines the array of U.S. states. If you have the European version of MapPoint, replacing this with County or Major City names should work fine.

The next section instantiates MapPoint and opens a new map. In Perl, Methods are called using the -> characters. In the for loop that follows, FindPlaceResults is used to bring up each state in the array, "GoTo" the states and then save an html file. Note the last lines, properties are set using the curly brackets {}.

That's it! The files that are produced include an html file and directory for each state and the image file itself is simply called image_map.gif. Perl is great and file and directory manipulation, it would be trivial to get 51 gif files with the name of the state such as North_Dakota.gif. Other Perl modules would give you ability to manipulate or re-size the image and ftp it to a location or otherwise send it somewhere, create a PDF document with the map, and more. The applications are endless, I would encourage any developer to peruse the available Perl modules and scripts on CPAN to add to your arsenal of programming tools.

This article originally appeared on MP2K Magazine.