php stay of user selection of radio button on refresh of form (due to error checking or other)
<p>This is my code</p>

<pre><code>&lt;input type="radio" name="rdNumber" value="100"&lt;?=(isset($_POST['rdNumber']) == 100 ? "checked" : "")?&gt;/&gt;100 
&lt;input type="radio" name="rdNumber" value="1000" checked="checked"/&gt;1000 
</code></pre>

<p>It does not work as required.. when the form is submitted (and in any case of error) it returns back to the default checked radio button i.e. with value = 1000 user has to again click on value = 100, while the target was, if user selected 100 radio button he shall stay with 100, not moved to defaultly checked (i.e. value = 1000)</p>

<p>Where am I wrong?
Also what would be the if else version of the same?</p>
