使用 IClientMessageInspector 重写 WCF 消息

>我正在调用供应商 Web 服务，其调用的架构需要在 body 标记中使用自定义命名空间，如下所示：

<s:Body xmlns:ddw="http://www.infinity.com/bpm/model/OmniLinkServices/DDWEBCallInput" 
        xmlns:omn="http://eclipse.org/stardust/models/generated/OmniLinkServices">

我

无法通过属性配置、绑定配置等找到添加此命名空间的好方法，因此我创建了一个 IClientMessageInspector 的实现来将命名空间添加到 body 标签中。 它有效，但随后消息的正文变为：

<s:Body xmlns:ddw="http://www.infinity.com/bpm/model/OmniLinkServices/DDWEBCallInput" 
   xmlns:omn="http://eclipse.org/stardust/models/generated/OmniLinkServices">
   ... stream ...
</s:Body>

注意奇怪的...流。。。正文的内容。

这是我对BeforeSendRequest IClientMessageInspector的实现

public object BeforeSendRequest(ref Message request, IClientChannel channel)
{
        //Copy old message into XPathNavigator so as first step in transforming it to (newer) XDocument for modification
        Message newMessage = null;
        MessageBuffer msgbuf = request.CreateBufferedCopy(int.MaxValue);
        XPathNavigator nav = msgbuf.CreateNavigator();
        //load the old message into message stream via XmlWriter
        MemoryStream ms = new MemoryStream();
        XmlWriter xw = XmlWriter.Create(ms);
        nav.WriteSubtree(xw);
        xw.Flush();
        xw.Close();
        ms.Position = 0;
        //load the XDocument from the XmlREader
        XDocument xDoc = XDocument.Load(XmlReader.Create(ms));
        ms.Close();
        //add the sungard namespaces to the body of the message
        var body = (from x in xDoc.Descendants() where x.Name.LocalName == "Body" select x).First();
        var ddwns = new XAttribute(XNamespace.Xmlns + "ddw", "http://www.infinity.com/bpm/model/OmniLinkServices/DDWEBCallInput");
        var omnns = new XAttribute(XNamespace.Xmlns + "omn", "http://eclipse.org/stardust/models/generated/OmniLinkServices");
        body.Add(ddwns);
        body.Add(omnns);
        //create the new message
        //write the XDoc back out to memory stream
        MemoryStream newMsg = new MemoryStream();
        xw = XmlWriter.Create(newMsg);            
        xDoc.Save(xw);
        xw.Flush();
        xw.Close();
        newMsg.Position = 0;
        //create the new message        
        XmlReader reader = XmlReader.Create(newMsg);
        newMessage = Message.CreateMessage(reader, int.MaxValue, request.Version);
        request = newMessage;
        return null;
}

在函数的最后，XDocument仍然具有有效的XML，但是当我在最后创建消息时，这似乎是问题发生的地方。

有人有什么想法吗？