is a string a valid timezone in .net
<p>I receive a string as a json parameter and it's supposed to be a timezone ID. I want to check for that.</p>

<p>This is what I have:</p>

<pre><code>TheTimezoneID = TheTimezoneID.Trim();
var AllTimezones = TimeZoneInfo.GetSystemTimeZones();

if (TheTimezoneID "is a valid .net timezone" == true) {}
</code></pre>

<p>What's the linq expression that'll test if TheTimezoneID is in AllTimezones? I tried using .Any but it's not working.</p>

<p>Thanks.</p>
