title: Append values to query string
body: <p>I have set of URLs similar to the ones below in a list</p>
  <ul>
  <li><code>http://somesite.example/backup/lol.php?id=1&amp;server=4&amp;location=us</code></li>
  <li><code>http://somesite.example/news.php?article=1&amp;lang=en</code></li>
  </ul>
  <p>I have managed to get the query strings using the following code:</p>
  <pre><code>myurl = longurl.Split('?');
  NameValueCollection qs = HttpUtility.ParseQueryString(myurl [1]);
  
  foreach (string lol in qs)
  {
      // results will return
  }
  </code></pre>
  <p>But it only returns the parameters like
  <strong>id</strong>, <strong>server</strong>, <strong>location</strong> and so on based on the URL provided.</p>
  <p>What I need is to add / append values to the existing query strings.</p>
  <p>For example with the URL:</p>
  <p><code>http://somesite.example/backup/index.php?action=login&amp;attempts=1</code></p>
  <p>I need to alter the values of the query string parameters:</p>
  <p><strong>action=login1</strong></p>
  <p><strong>attempts=11</strong></p>
  <p>As you can see, I have appended &quot;1&quot; for each value. I need to get a set of URLs from a string with different query strings in them and add a value to each parameter at the end &amp; again add them to a list.</p>