How can use Group by in linq with XML file

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.IO;

//***Add below class for XElement

using System.Xml;

using System.Text;

using System.Xml.Linq;

/*LINQ—language integrated query—introduces many extensions methods to the standard C# environment. 

  These methods work on Lists, arrays and collections that are not yet in memory. 

*/

public partial class Linq : System.Web.UI.Page

{

    protected void Page_Load(object sender, EventArgs e)

    {

      

        test();

    }

   private void test()

    {

        XDocument doc = XDocument.Parse(@"<root>

  <RoomRates>

      <RoomPurchaseToken>73516</RoomPurchaseToken>

      <RoomCode>sgl</RoomCode>

      <RoomType>Single Standard Room Bed and Breakfast</RoomType>

      <Adults>45</Adults>

      <Children>0</Children>

      <Quantity>1</Quantity>

      <Price>1255</Price>

      <CurrencyCode>USD</CurrencyCode>

      <Type>Available</Type>

      <OfferType />

      <HotelCode>35</HotelCode>

    </RoomRates>

 <RoomRates>

      <RoomPurchaseToken>73517</RoomPurchaseToken>

      <RoomCode>sgl</RoomCode>

      <RoomType>Single Deluxe Room  Bed and Breakfast</RoomType>

      <Adults>1</Adults>

      <Children>0</Children>

      <Quantity>1</Quantity>

      <Price>127</Price>

      <CurrencyCode>USD</CurrencyCode>

      <Type>Available</Type>

      <OfferType />

      <HotelCode>35</HotelCode>

    </RoomRates>

 <RoomRates>

      <RoomPurchaseToken>734532203</RoomPurchaseToken>

      <RoomCode>sgl</RoomCode>

      <RoomType>Single Deluxe Rooms  Bed and Breakfast</RoomType>

      <Adults>1</Adults>

      <Children>0</Children>

      <Quantity>1</Quantity>

      <Price>158</Price>

      <CurrencyCode>USD</CurrencyCode>

      <Type>Available</Type>

      <OfferType />

      <HotelCode>88932</HotelCode>

    </RoomRates>

    <RoomRates>

      <RoomPurchaseToken>734532204</RoomPurchaseToken>

      <RoomCode>sgl</RoomCode>

      <RoomType>Single Premium Rooms  Bed and Breakfast</RoomType>

      <Adults>1</Adults>

      <Children>0</Children>

      <Quantity>1</Quantity>

      <Price>176</Price>

      <CurrencyCode>USD</CurrencyCode>

      <Type>Available</Type>

      <OfferType />

      <HotelCode>88932</HotelCode>

    </RoomRates>

    <RoomRates>

      <RoomPurchaseToken>734532205</RoomPurchaseToken>

      <RoomCode>sgl</RoomCode>

      <RoomType>Single Junior Suites  Bed and Breakfast</RoomType>

      <Adults>1</Adults>

      <Children>0</Children>

      <Quantity>1</Quantity>

      <Price>223</Price>

      <CurrencyCode>USD</CurrencyCode>

      <Type>Available</Type>

      <OfferType />

      <HotelCode>88932</HotelCode>

    </RoomRates>

    <RoomRates>

      <RoomPurchaseToken>734532207</RoomPurchaseToken>

      <RoomCode>sgl</RoomCode>

      <RoomType>Single Executive Suites Bed and Breakfast</RoomType>

      <Adults>1</Adults>

      <Children>0</Children>

      <Quantity>1</Quantity>

      <Price>295</Price>

      <CurrencyCode>USD</CurrencyCode>

      <Type>On Request</Type>

      <OfferType />

      <HotelCode>88932</HotelCode>

    </RoomRates>

</root>");

        var query =

                from RoomRates in doc.Root.Elements("RoomRates")

                group RoomRates by (int)RoomRates.Element("HotelCode") into g1

                select new

                {

                    HotelCode = g1.Key,

                    AllValues = from alldata in g1

                                //from alldata in g1.Elements("Price")

                                //select (string)alldata

                                select new 

                                {

                                    price = (string)alldata.Element("Price"),

                                    Children = (string)alldata.Element("Children"),

                                    CurrencyCode = (string)alldata.Element("CurrencyCode"),

                                }

                };

        

            foreach (var item in query)

            {

                Response.Write("Key:" + item.HotelCode+ "</br>");

                foreach (var alldata in item.AllValues)

                {

                    Response.Write(alldata + "</br>");

                }

                Console.WriteLine();

            }

        }

    }

OUTPUT:

Key:35
{ price = 1255, Children = 0, CurrencyCode = USD }
{ price = 127, Children = 0, CurrencyCode = USD }
Key:88932
{ price = 158, Children = 0, CurrencyCode = USD }
{ price = 176, Children = 0, CurrencyCode = USD }
{ price = 223, Children = 0, CurrencyCode = USD }
{ price = 295, Children = 0, CurrencyCode = USD }