If you mean adding a button that once clicked will delete a file you need to have abit of HTML added, so just use this.
PHP Code:
<?
if(isset($_POST['submit']{
$file_delete = "A_Picture.jpg";
if (unlink($file_delete)) {
echo "The file was deleted successfully.", "\n";
} else {
echo "The specified file could not be deleted. Please try again.", "\n";
}
}?>
<form method="post">
<input type="submit" name="submit" Value="Delete">
</form>
Hope this helps!