title: String to Numeric conversion and group separator
body: <p>When I try to convert a string to a numeric value with Parse or TryParse or Convert.ChangeType, I can't manage de thousand separator as it is defined in the system:</p>
  
  <p>if I enter :</p>
  
  <pre><code>var d = double.Parse("1,234", CultureInfo.CurrentUICulture);
  </code></pre>
  
  <p>it does not return 1234.</p>
  
  <p>If I want to use the group separator, I must type :</p>
  
  <pre><code>var d = double.Parse("1,234", NumberStyles.Number, CultureInfo.CurrentUICulture);
  </code></pre>
  
  <p>This time, the result is that one expected.</p>
  
  <p>But, I don't want to force the use of the thousand separator, I want use it only if the system specify it in the globalization settings. Is there a way to know if the separator is used (I know that I can read the group separator in <code>CultureInfo.CurrentUICulture.NumberFormat.NumberGroupSeparator</code>)</p>
  
  <p>Cheers
  Loic</p>