通过web.config设置网站默认页

<configuration>     <system.web>         <compilation debug="true" targetFramework="4.0" />     </system.web>   <appSettings>   </appSettings>   <system.webServer>     <defaultDocument>       <files>         <clear />         <add value="index.aspx" />       </files>     </defaultDocument>   </system.webServer> </configuration>