AdCreatedEventHandler.aspx font size:
C# Source: AdCreatedEventHandler.aspx   banners.xml   
<html>
<head>
<title>AdCreated Event Handler Example</title>
<link rel="stylesheet" href="/shared/netdemos.css">

<script language="C#" runat="server">
void AdCreatedHandler ( Object src, AdCreatedEventArgs e ) {
   string props = "<b>Ad properties</b><br>";
   props += "<b>Image File</b>: " + e.ImageUrl + "<br>";
   props += "<b>Alternate Text</b>: " + e.AlternateText + "<br>";
   props += "<b>Navigate URL </b>: " + e.NavigateUrl + "<br>";
   adProps.Text = props;
}
</script>
</head>

<body>
<!-- #include virtual="~/shared/top.inc -->
<div class="header"><h2>AdCreated Event Handler Example</h2></div>

<!-- #include virtual="~/shared/viewsrc_top.inc" -->
<hr size=1 width=92%>

<form runat=server>
<div align="center">

   <asp:adrotator id="AdRotator1" runat="server"
      advertisementfile="~/webforms/demos/banners.xml"
      borderwidth=1 target="_blank"
      onAdCreated="AdCreatedHandler"/>

   <p><input type=submit value="Reload" runat="server"></p>

   <asp:label id="adProps" runat="server" /></p>

</form>
</div>

<hr size=1 width=92%>
<!-- #include virtual="~/shared/viewsrc.inc" -->

</body>
</html>