Extraction Rule]

 


Hi Group ,
I'm using VSTS 2008 to teast my project ,,
I want to ask about extraction rule ,, the built in and custom , i learend what each built
in extraction rule did [extract hhtp header, extract text ,....etc] but till now what the exact
use of them and if i write a custom extraction rule to Extract query string parameter ,, what
the useful that i can get from it ,,,
I mean how extraction Rule helps my webtest??

 

Thanks In advance :)
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