Incrementing session variables

Hi Simon,

If this is the script that invokes your scraping session you'll probably just want to set the initial value. I'd recommend changing it like so:


runnableScrapingSession = new com.screenscraper.scraper.RunnableScrapingSession( "Test6" );

runnableScrapingSession.setVariable( "FromRec", new Integer());

runnableScrapingSession.scrape();

It's more likely that in subsequent scripts you'll want to increment the value. That is, for subsequent search results pages you'll want to increment the record offset, so you might execute a script like the following:

session.log( "FromRec (before increment): " + session.getVariable( "FromRec" ));

session.setVariable
(
"FromRec",
new Integer
(
(( Integer )session.getVariable( "FromRec" )).intValue()
+ 10
)
);

session.log( "FromRec (after increment): " + session.getVariable( "FromRec" ));

So the first URL might look like this:

http://www.example.com/go.cfm?FromRec=1&tab=&keyword=&search=yes&format=2

After that URL is requested you would run the second script, which would make the URL this:

http://www.example.com/go.cfm?FromRec=11&tab=&keyword=&search=yes&format=2

Hopefully that makes sense. If not, please feel free to post back.

Best,

Todd
[email protected]

That's fantastic, Simon! If you're truly a non-programmer that's great that you've already been so successful with screen-scraper.

As it turns out, incrementing the value isn't as straightforward as it seems like it should be, and it's something that others have asked about, so it's understandable that it would seem confusing. Here's a snippet of code that demonstrates how you would do it using Interpreted Java:

session.setVariable( "FromRec", new Integer( 1 ));

session.log( "FromRec (before increment): " + session.getVariable( "FromRec" ));

session.setVariable
(
"FromRec",
new Integer
(
(( Integer )session.getVariable( "FromRec" )).intValue()
+ 10
)
);

session.log( "FromRec (after increment): " + session.getVariable( "FromRec" ));

The difficulty is that everything must be treated as an object in Java, so it requires a bit of casting to make it work. If it helps at all, we actually have on our to-do list to create a shortcut method for this kind of thing. Watch of it in a future version of screen-scraper.

Using this approach, your URL would then look something like this:

http://www.example.com/go.cfm?FromRec=~#FromRec#~&tab=&keyword=&search=yes&format=2

Hopefully this helps to keep the ball rolling for you. Don't hesitate to post again if we can be of further assistance.

Kind regards,

Todd Wilson
[email protected]