Why doesn't my code compile? 
<p>I am using regular expression in code behind file and defining string as</p>

<pre><code>string ValEmail = "\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*";

if (Regex.IsMatch(email, "\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*"))
{  }
else
{  }
</code></pre>

<p>It gives me warning and does not compile. How can I define such string combination?.</p>

<p>Any help is appreciated</p>
