title: control class treatment progress from another class
body: <p>i hope i get sucess my explanation.</p>
  
  <p>I am designing a console application for a POC software (proof of concept) with minimal functionnalities as follow : </p>
  
  <pre><code>[Class 1]
  1- Timer run each 60 seconds.
  2- download an xml file over http (WebClient)
  3- parse IDs (ID of metadata xml file inside the same http server)
  4- Enqueue the queue by IDs in Class 2 [Queue&lt;string&gt; _downloadUrls = new Queue&lt;string&gt;()]
  [Class 2 ]
  5- Dequeue urls and start download each file whithin teh queue
  6- Deserialize the xml to a valid reference an d save it into Database
  </code></pre>
  
  <p>Question :</p>
  
  <p>How can i tell the timer in Class1 to escape treatement if download of files in Class2 is still in progress (can take more time than Timer peridicity interval).</p>
  
  <p>N.B : download is asynchronosly.</p>
  
  <p>Regards</p>