x-www-form-urlencoded传参，body的KEY: Message，VALUE: <OTA_InventoryCheckRQ EchoToken="487ef6b0-3526-45e3-81e7-0eac31754c10" Password="abc888888" PrimaryLangID="en-us" TimeStamp="2021-04-20 10:30:59" UserName="guowang" Version="1.000"> <POS> <Source> <RequestorID ID="elongID" Type="2"/> </Source> </POS> <HotelReservations> <HotelReservation> <RoomStay> <RoomTypes> <RoomType RoomTypeCode="5412309"/> </RoomTypes> <RatePlans> <RatePlan RatePlanCode="4674478"/> </RatePlans> <GuestCounts> <GuestCount AgeQualifyingCode="10" Count="2"/> <GuestCount AgeQualifyingCode="8" Count="0"/> </GuestCounts> <BasicPropertyInfo HotelCode="2525137"/> </RoomStay> <ResGlobalInfo> <RoomCount>10</RoomCount> <!-- 会员登记-开关露出 --> <MemberLevel>V1</MemberLevel> <TimeSpan End="2021-04-30" Start="2021-04-29"/> </ResGlobalInfo> </HotelReservation> </HotelReservations> </OTA_InventoryCheckRQ>，.net core接收的实体模型

可以定义一个实体模型来接收 x-www-form-urlencoded 格式的参数。根据你提供的参数，可以定义如下的实体模型：

public class InventoryCheckRequest
{
    public string EchoToken { get; set; }
    public string Password { get; set; }
    public string PrimaryLangID { get; set; }
    public string TimeStamp { get; set; }
    public string UserName { get; set; }
    public string Version { get; set; }
    public POS POS { get; set; }
    public HotelReservations HotelReservations { get; set; }
}

public class POS
{
    public Source Source { get; set; }
}

public class Source
{
    public RequestorID RequestorID { get; set; }
}

public class RequestorID
{
    public string ID { get; set; }
    public string Type { get; set; }
}

public class HotelReservations
{
    public HotelReservation HotelReservation { get; set; }
}

public class HotelReservation
{
    public RoomStay RoomStay { get; set; }
    public ResGlobalInfo ResGlobalInfo { get; set; }
}

public class RoomStay
{
    public RoomTypes RoomTypes { get; set; }
    public RatePlans RatePlans { get; set; }
    public GuestCounts GuestCounts { get; set; }
    public BasicPropertyInfo BasicPropertyInfo { get; set; }
}

public class RoomTypes
{
    public RoomType RoomType { get; set; }
}

public class RoomType
{
    public string RoomTypeCode { get; set; }
}

public class RatePlans
{
    public RatePlan RatePlan { get; set; }
}

public class RatePlan
{
    public string RatePlanCode { get; set; }
}

public class GuestCounts
{
    public List<GuestCount> GuestCount { get; set; }
}

public class GuestCount
{
    public string AgeQualifyingCode { get; set; }
    public int Count { get; set; }
}

public class BasicPropertyInfo
{
    public string HotelCode { get; set; }
}

public class ResGlobalInfo
{
    public int RoomCount { get; set; }
    public string MemberLevel { get; set; }
    public TimeSpan TimeSpan { get; set; }
}

public class TimeSpan
{
    public DateTime End { get; set; }
    public DateTime Start { get; set; }
}

在控制器中，可以使用以下代码将 x-www-form-urlencoded 格式的参数转换成实体模型：

using System;
using System.IO;
using System.Net;
using System.Text;
using System.Xml.Serialization;
using Microsoft.AspNetCore.Mvc;

public class TestController : Controller
{
    [HttpPost]
    public IActionResult ReceiveMessage()
    {
        using (StreamReader reader = new StreamReader(Request.Body, Encoding.UTF8))
        {
            string bodyStr = reader.ReadToEnd();
            string message = WebUtility.UrlDecode(bodyStr.Substring(8));
            // 将 message 转换成实体模型
            XmlSerializer serializer = new XmlSerializer(typeof(InventoryCheckRequest));
            using (StringReader stringReader = new StringReader(message))
            {
                InventoryCheckRequest request = (InventoryCheckRequest)serializer.Deserialize(stringReader);
                // 对实体模型进行处理
            }
            return Ok();
        }
    }
}

在上面的代码中，使用了 XmlSerializer 来将 XML 格式的字符串转换成实体模型。需要注意的是，实体模型中的 DateTime 类型需要在 XML 中使用 ISO 8601 格式表示。