title: How to concatenate array of integers into comma separated string
body: <p>I have two question, acually:</p>
  
  <ol>
  <li>How to join array of integers into comma separated string? 
  <em>(1,2,3) => "1,2,3"</em></li>
  <li>How to convert array of integers to array of string? <em>(1,2,3) => ("1", "2", "3")</em></li>
  </ol>
  
  
  
  <pre><code>$arraylist = New-Object 'system.collections.arraylist'
  $arraylist.Add(1);
  $arraylist.Add(2);
  
  $csv = ?? 
  #($arraylist-join -',') returns error: Cannot convert value "," to type "System.Int32". Error: "Input string was not in a correct format."
  </code></pre>