Web API-XML前綴

Question

美好的一天，通過使用Web API，我需要獲取以下xml響應（帶有所有前綴）：

  <test xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:ai="www.something.org">
    <ai:name>Ann</name>
    </test>

這是課程：

[XmlRoot(ElementName = "test")]
    public class Test
    {
        [XmlAttribute(AttributeName = "ai")]
        public const string Ai = "www.something.org";
        [XmlElement(ElementName = "name",Namespace = Ai)]
        public string Name { get; set; }

        public Test(string name)
        {
            Name = name;
        }
        public Test() { }
    }

問題是，如果您自己使用xmlSerializer，則可以使用

XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
ns.Add("ai", "www.something.org");

但是在這里，序列化是由Web api請求本身進行的：

[HttpGet]
[Route("test")]
public Test Testing()
{
 return new Test("Ann");
}

我得到的是沒有ai屬性，也沒有名稱空間的前綴。

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
    <name xmlns="www.something.org">
    Ann
    </name>

---

編輯。 如果我覆蓋XmlMediaTypeFormatter ，我將獲得正確的xml響應：

public class CustomXmlFormatter : XmlMediaTypeFormatter
    {
        public override Task WriteToStreamAsync(Type type, object value, Stream writeStream, HttpContent content,
            TransportContext transportContext)
        {
            var serializer = new XmlSerializer(type);
            XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
            ns.Add("ai", "www.something.org");

            return Task.Factory.StartNew(() =>
            {
                using (var streamWriter = new StreamWriter(writeStream, Encoding.UTF8))
                {
                    serializer.Serialize(streamWriter, value,ns);
                }
            });
            return base.WriteToStreamAsync(type, value, writeStream, content, transportContext);
        }
    }

但是 ，如果我有2個請求，那么每個請求都有不同的命名空間-但是此格式化程序將始終顯示兩個請求。 有什么辦法可以刪除未使用的名稱空間？

Answer 1

如果您像這樣定義您的自定義xml格式器：

public class CustomXmlFormatter : XmlMediaTypeFormatter
{
    public XmlSerializerNamespaces Namespaces { get; }

    public CustomXmlFormatter()
    {
        Namespaces = new XmlSerializerNamespaces();
    }

    public override Task WriteToStreamAsync(Type type, object value, System.IO.Stream writeStream, HttpContent content, TransportContext transportContext)
    {
        var serializer = new XmlSerializer(type);

        var xmlWriter = new XmlTextWriter(writeStream, Encoding.UTF8)
        {
            Namespaces = true
        };

        serializer.Serialize(xmlWriter, value, Namespaces);

        return Task.FromResult(true);
    }
}

然后，您可以創建一個使用此格式化程序的IControllerConfiguration並添加您的命名空間：

public class MyControllerConfig : Attribute, IControllerConfiguration
{
    private readonly string _prefix;
    private readonly string _ns;

    public MyControllerConfig(string prefix, string ns)
    {
        _prefix = prefix;
        _ns = ns;
    }

    public void Initialize(HttpControllerSettings controllerSettings,
                            HttpControllerDescriptor controllerDescriptor)
    {
        var formatter = new CustomXmlFormatter { UseXmlSerializer = true };
        formatter.Namespaces.Add(_prefix, _ns);
        controllerSettings.Formatters.Clear();
        controllerSettings.Formatters.Add(formatter);
    }
}

然后在您的控制器上使用它：

[MyControllerConfig("ai", Ns.Ai)]
public class MyController : ApiController
{
    [HttpGet]
    [Route("test")]
    public IHttpActionResult Testing()
    {
        return Ok(new Test("Ann"));
    }
}

public class Ns
{
    public const string Ai = "www.something.org";
}

[XmlRoot(ElementName = "test")]
public class Test
{
    [XmlElement(ElementName = "name", Namespace = Ns.Ai)]
    public string Name { get; set; }

    public Test(string name)
    {
        Name = name;
    }
    public Test() { }
}