title: Convert.ToDouble raises a FormatException
body: <p>how can i skip a &quot;System.FormatException&quot; ?</p>
  <p>Example:</p>
  <pre><code>    public void HowMuchBookCar()
      {
          Console.Write(&quot;\nOk, how much Euros you want to book in 'CarAndBeauty':  &quot;);
          double howMuch = Convert.ToDouble(Console.ReadLine());
          CarAndBeauty = Input(CarAndBeauty, howMuch);
          Save(@&quot;C:\Users\tobia\Desktop\Neuer Ordner\JanuaryCategorie.txt&quot;);
          Console.Clear();
          WannaBook();
      }
  </code></pre>
  <p>This method is to book a specific amount into the categorie &quot;Car &amp; Beauty&quot;.
  If the user would type here for example &quot;G&quot; (or something that does not work with this variable) it throws &quot;System.FormatException&quot; and the program stop working...</p>
  <p>That makes sense ... but how can I prevent the exception from being thrown and instead a specific code?
  (for example: &quot;please make valid entry!&quot;)</p>