How to check if variable is null, but allow 1 and 0?
<p>I use the following code currently</p>

<pre><code>if (oldValue) ...
</code></pre>

<p>It works well in case <code>oldValue</code> is <code>null</code>, but in case it is 0, it also returns <code>false</code>, when I expect <code>true</code>. So, how should I check for <code>null</code> value? I was thinking about </p>

<pre><code>if (oldValue!=null) ...
</code></pre>

<p>but it doesn't work as I've expected.</p>
