How to trigger a file download when clicking an HTML button or JavaScript

Question

This is crazy but I don\'t know how to do this, and because of how common the words are, it\'s hard to find what I need on search engines. I\'m thinking this should be an ea

Answer 1

Another way of doing in case you have a complex URL such as file.doc?foo=bar&jon=doe is to add hidden field inside the form

  
  
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inspired on @Cfreak answer which is not complete