如果请求的地址为
http://www.cnblogs.com/default.aspx/books
则 Request.PathInfo 值为 /books
Request.Path 值为 http://www.cnblogs.com/default.aspx/books
Request.RawUrl 值为 http://www.cnblogs.com/default.aspx/books
如果请求地址为
http://www.cnblogs.com/defaut.aspx?id=1&name=kk
则 Request.PathInfo 值为 ""(空字符串)
Request.Path 值为 http://www.cnblogs.com/default.aspx
Request.RawUrl 值为 http://www.cnblogs.com/default.aspx?id=1&name=kk