e></div>

<h4>Notes</h4>
<ol>
<li><b>EmptyConstraint</b> creates and uses either an <b>EmptyStringConstraint</b>,
<b>EmptyDirectoryConstraint</b> or <b>EmptyCollectionConstraint</b> depending on
the argument tested.
<li>A <b>DirectoryInfo</b> argument is required in order to test for an empty directory.
To test whether a string represents a directory path, you must first construct
a <b>DirectoryInfo</b>.
</ol>

<h3>UniqueItemsConstraint</h3>

<h4>Action</h4>
<p>Tests that an array, collection or other IEnum