Suggestions for coding language

I am making a calendar that uses an HTML form to filter information from it with check boxes. I want the days in the calendar populated with information from an XML (the XML info is what will be filtered with the check boxes). I’ve been creating it using HTML and JavaScript so far, but I’m wondering if it would be easier to code with another language like ASP. The problem I am having is figuring out how to get JS variables for each day in my HTML made calendar table, and having the JS array variable filled with information from the XML file for each day of the month.