How do I send dynamic POST parameters in screen-scraper?

If you've gone through our first few tutorials, you know that session variables can be embedded in URL's by using a token like this: ~#FOO#~ (see this page for a detailed example of this). Well, the very same technique can be used with POST variables. When you create a scrapeable file that uses POST parameters, they'll be displayed under the "Parameters" tab for that scrapeable file. In any of those POST parameters you can use the same type of token mentioned before. For example, if you're logging in to a web site (as described here), instead of hard-coding the username and password, you might instead substitute the tokens ~#USERNAME#~ and ~#PASSWORD#~ in the "Value" column, for the respective parameters. Prior to invoking that scrapeable file, you could then set two session variables corresponding to the username and password, which values would then be substituted for the ~#USERNAME#~ and ~#PASSWORD#~ tokens.