title: How to check if a String is an Int in Swift?
body: <p>I have a TextField which I want to verify if the inputted text is an integer. How could I do this?</p>
  
  <p>I want to write a function like this:</p>
  
  <pre><code>func isStringAnInt(string: String) -&gt; Bool {
  
  }
  </code></pre>