如何从Web API XML序列化程序中删除xmlns：xsi和xmlns：xsd

Question

几个小时以来，我一直在努力从ASP.NET Web Api中序列化我的独立对象（不是MVC模型）返回的XML中删除默认命名空间。该应用程序的示例代码是：

类定义：

public class PaymentNotificationResponse
{

    [XmlArray("Payments")]
    [XmlArrayItem("Payment", typeof(PaymentResponse))]
    public PaymentResponse[] Payments { get; set; }
}

然后我创建了一个Web Api Controller，它根据一些输入创建了PaymentNotificationResponse的对象，然后将对象序列化到请求方。控制器如下：

public class PaymentController : ApiController
{

    public PaymentNotificationResponse Post()
    {
        //Read request content (only available async), run the task to completion and pick the stream.
        var strmTask = Request.Content.ReadAsStreamAsync();
        while (strmTask.Status != TaskStatus.RanToCompletion) { }
        Stream strm = strmTask.Result;

        //Go back to the beginning of the stream, so that the data can be retrieved. Web Api reads it to the end.
        if (strm.CanSeek)
            strm.Seek(0, SeekOrigin.Begin);

        //Read stream content and convert to string.
        byte[] arr = new byte[strm.Length];
        strm.Read(arr, 0, arr.Length);
        String str = Encoding.UTF8.GetString(arr);

        //Change the default serializer to XmlSerializer from DataContractSerializer, so that I don't get funny namespaces in properties.
        //Then set a new XmlSerializer for the object
        Configuration.Formatters.XmlFormatter.UseXmlSerializer = true;
        Configuration.Formatters.XmlFormatter.SetSerializer<PaymentNotificationResponse>(new XmlSerializer(typeof(PaymentNotificationResponse)));

        //Now call a function that would convert the string to the required object, which would then be serialized when the Web Api is invoked.
        return CreatePaymentNotificationFromString(str);
    }
}

问题是，当我用有效的字符串参数调用Api时，它返回这种格式的XML（有效的XML，但不需要xmlns）：

<PaymentNotificationResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
    <Payments>
        <Payment>
            <PaymentLogId>8325</PaymentLogId>
            <Status>0</Status>
        </Payment>
    </Payments>
</PaymentNotificationResponse>

我发送给它的系统不需要xmlns:xsi和xmlns:xsd。实际上，它在看到名称空间时会返回异常。

我尝试使用XML标签返回一个字符串，它只是将响应包装在<string></string>中并编码所有<和>。所以这不是一个选择。

我看到了this post和this one。虽然前者非常详细，但它并没有解决我的问题。它只是在生成的XML中引入了一个额外的xmlns。我认为这是因为我没有明确地在.Serialize()中调用XmlSerializer函数。

我想出了一个解决方案，我想我应该分享。所以我会在答案中说明。

Answer 1

为了解决这个问题，我添加了一个序列化PaymentNotificationResponseand的方法返回一个XML字符串，因此（我将其包含在PaymentNotificationResponse的定义中）：

//I added this method after I tried serialize directly to no avail
    public String SerializeToXml()
    {
        MemoryStream ms = new MemoryStream();

        XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
        ns.Add("", "");

        new XmlSerializer(typeof(PaymentNotificationResponse)).Serialize(ms, this, ns);
        XmlTextWriter textWriter = new XmlTextWriter(ms, Encoding.UTF8);

        ms = (System.IO.MemoryStream)textWriter.BaseStream;

        return new UTF8Encoding().GetString(ms.ToArray());
    }

我解析了字符串以创建XDocument，然后返回根元素。这使我将Post()方法的返回类型更改为XElement。然后Post()列表将是：

public XElement Post()
    {
        //...Same as it was in the question, just the last line that changed.

        var pnr = CreatePaymentNotificationFromString(str);
        return XDocument.Parse(pnr.SerializeToXml()).Root;
    }

这将使我的响应XML：

<PaymentNotificationResponse>
    <Payments>
        <Payment>
            <PaymentLogId>8325</PaymentLogId>
            <Status>0</Status>
        </Payment>
    </Payments>
</PaymentNotificationResponse>

我希望这可以帮助别人。