StartsWith in Expression return null
<p>Could somone tell me why this statement return nothing and how to correct it. What im trying todo is select User where username starts with the letter from the alphabet</p>

<p>alpha = "A" "B" "C" "D" etc.
both don't work</p>

<pre><code>IList&lt;MembershipUser&gt; users = Membership.GetAllUsers().Cast&lt;MembershipUser&gt;()
.Where(x =&gt; x.UserName.StartsWith(alpha) == true).ToList();

IList&lt;MembershipUser&gt; users = Membership.GetAllUsers().Cast&lt;MembershipUser&gt;()
.Where(x =&gt; x.UserName.StartsWith(alpha)).ToList();
</code></pre>
