Why do my radiobuttons have "not in this current context" error when in my if statements?
<p>My radio buttons don't appear when I type them in the <code>if</code> statements it gives me:</p>

<blockquote>
  <p>The name "Activity" does not appear in this current context.</p>
</blockquote>

<p>(html)</p>

<pre><code>&lt;div class="option"&gt;
    &lt;input id="Activity1" value="Activity1" name="Activity" checked="" type="radio" /&gt;
    &lt;label for="Activity1"&gt;Light Activity &lt;br /&gt;(Moderate excercise, &lt;br /&gt; but inactive at work)&lt;/label&gt;
&lt;/div&gt;
&lt;div class="option"&gt;
    &lt;input id="Activity2" value="Activity2" name="Activity" checked="" type="radio" /&gt;
    &lt;label for="Activity2"&gt;Moderate Activity &lt;br /&gt;(Intense excercise, &lt;br /&gt; but inactive at work)&lt;/label&gt;
&lt;/div&gt;
&lt;div class="option"&gt;
    &lt;input id="Activity3" value="Activity3" name="Activity" checked="" type="radio" /&gt;
    &lt;label for="Activity3"&gt;Very Active &lt;br /&gt;(Moderate excercise,&lt;br /&gt; active job)&lt;/label&gt;
&lt;/div&gt;
&lt;div class="option"&gt;
    &lt;input id="Activity4" value="Activity4" name="Activity" checked="" type="radio" /&gt;
    &lt;label for="Activity4"&gt;Extremely Active &lt;br /&gt;(Intense excercise, &lt;br /&gt; active job)&lt;/label&gt;
&lt;/div&gt;
</code></pre>

<hr>

<p>(c#)</p>

<pre><code>if (Activity.Activity1.checked)
{
    //initialise the activity levels
    //take uBW and aL and multiply and put sum in usercarb
    activityLevel = 11;
    UserCal = (UserBodyWeight * activityLevel);
}
else if (Activity.Activity2.checked)
{
    activityLevel = 12;
    UserCal = (UserBodyWeight * activityLevel);    
}
</code></pre>