title: Replace item in querystring
body: <p>I have a URL that also might have a query string part, the query string might be empty or have multiple items.</p>
  
  <p>I want to replace one of the items in the query string or add it if the item doesn't already exists.</p>
  
  <p>I have an URI object with the complete URL.</p>
  
  <p>My first idea was to use regex and some string magic, that should do it. </p>
  
  <p>But it seems a bit shaky, perhaps the framework has some query string builder class?</p>