Web Download Activity out put parameters

Hi Team, 

For one of the campaigns, I am using web download activity and in my case the output or responses are stored in the .html file. 

Something like this xyz_<datetimestamp>.html . 

Can I get some help to retrieve the data stored in the html file either from javascript. 

Or can i change the way the output is stored, like a csv file may be. 

Thanks,
Adithya