title: Convert an object to string array at runtime
body: <p>I have a line in my code:</p>
  
  <pre><code>var objects = ExternalApiGetObjects(....);
  </code></pre>
  
  <p>At develop time I only know that <code>ExternalApiGetObjects</code> returns an <code>Object</code> instance. In fact, I'm sure that <code>objects</code> variable is an array of some type.
  I want to pass <code>objects</code> variable to <code>String.Join</code> method, but in runtime I got an exception similar to this: "Object of type 'System.Int32[]' cannot be converted to type 'System.String[]'."</p>
  
  <p>In most cases, an <code>objects</code> will not be a string array. It could be an int array, or even an array of some user's type. I just know that objects is an array and I want to invoke <code>ToString()</code> on each item of that array to create a new one with type of <code>string[]</code>.</p>
  
  <p>How can I convert my <code>objects</code> to <code>string[]</code>?</p>