Question

我正在使用DataContractSerializer将对象序列化为XML。主要对象是具有名称空间“http://personaltrading.test.com/”的SecurityHolding，并包含名为Amount的属性，该属性是名为“http://core.test.com”的类。当我将其序列化为XML时，我得到以下内容：

<ArrayOfSecurityHolding xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://personaltrading.test.com/">
  <SecurityHolding>
    <Amount xmlns:d3p1="http://core.test.com/">
        <d3p1:Amount>1.05</d3p1:Amount>
        <d3p1:CurrencyCode>USD</d3p1:CurrencyCode>
    </Amount>
    <BrokerageID>0</BrokerageID>
    <BrokerageName i:nil="true" />
    <RecordID>3681</RecordID>
  </SecurityHolding></ArrayOfSecurityHolding>

无论如何我可以控制d3p1前缀吗？我做错了什么或者我应该做些什么？

Answer 1

首先，命名空间别名的选择应该与格式良好的解析器没有区别。

但;它必须是DataContractSerializer吗？使用XmlSerializer，您可以使用接受Serialize的{{1}}重载。这允许您选择和使用您使用的命名空间和别名。

最终; XmlSerializerNamespaces 不旨在提供完整的xml控件;这不是它的目标。如果你想要严格的xml控制，DataContractSerializer是一个更好的选择，即使它更老（并且有自己的一些细微差别/弱点）。

完整示例：

XmlSerializer

输出：

using System;
using System.Xml.Serialization;
public class Amount
{
    public const string CoreNamespace = "http://core.test.com/";
    [XmlElement("Amount", Namespace=CoreNamespace)]
    public decimal Value { get; set; }
    [XmlElement("CurrencyCode", Namespace = CoreNamespace)]
    public string Currency { get; set; }
}
[XmlType("SecurityHolding", Namespace = SecurityHolding.TradingNamespace)]
public class SecurityHolding
{
    public const string TradingNamespace = "http://personaltrading.test.com/";

    [XmlElement("Amount", Namespace = Amount.CoreNamespace)]
    public Amount Amount { get; set; }

    public int BrokerageId { get; set; }
    public string BrokerageName { get; set; }
    public int RecordId { get; set; }
}
static class Program
{
    static void Main()
    {
        var data = new[] {
            new SecurityHolding {
                Amount = new Amount {
                    Value = 1.05M,
                    Currency = "USD"
                },
                BrokerageId = 0,
                BrokerageName = null,
                RecordId = 3681
            }
        };
        var ser = new XmlSerializer(data.GetType(),
            new XmlRootAttribute("ArrayOfSecurityHolding") { Namespace = SecurityHolding.TradingNamespace});
        var ns = new XmlSerializerNamespaces();
        ns.Add("foo", Amount.CoreNamespace);
        ser.Serialize(Console.Out, data, ns);
    }
}

Answer 2

我已经解决了这个问题与Marc略有不同，可以在基类中实现。

创建一个新属性以定义您将在数据协定中使用的其他XML命名空间。

[AttributeUsage(AttributeTargets.Class, Inherited = true, AllowMultiple = true)]    
public sealed class NamespaceAttribute : Attribute    
{   

    public NamespaceAttribute()
    {
    }

    public NamespaceAttribute(string prefix, string uri)
    {
        Prefix = prefix;
        Uri = uri;
    }

    public string Prefix { get; set; }
    public string Uri { get; set; }
}

将属性添加到数据合同中。

[DataContract(Name = "SomeObject", Namespace = "http://schemas.domain.com/namespace/")]    
[Namespace(Prefix = "a", Uri = "http://schemas.microsoft.com/2003/10/Serialization/Arrays")]    
[Namespace(Prefix = "wm", Uri = "http://schemas.datacontract.org/2004/07/System.Windows.Media")]           
public class SomeObject : SerializableObject          
{    

    private IList<Color> colors;

    [DataMember]
    [DisplayName("Colors")]
    public IList<Colors> Colors
    {
        get { return colors; }
        set { colours = value; }
    }
}

然后在Save方法中，使用反射来获取属性，然后将它们写入文件。

public static void Save(SerializableObject o, string filename)
{
    using (Stream outputStream = new FileStream(filename, FileMode.Create, FileAccess.Write))
    {
        if (outputStream == null)
            throw new ArgumentNullException("Must have valid output stream");

        if (outputStream.CanWrite == false)
            throw new ArgumentException("Cannot write to output stream");

        object[] attributes;
        attributes = o.GetType().GetCustomAttributes(typeof(NamespaceAttribute), true);    

        XmlWriterSettings writerSettings = new XmlWriterSettings();                
        writerSettings.Indent = true;
        writerSettings.NewLineOnAttributes = true;                
        using (XmlWriter w = XmlWriter.Create(outputStream, writerSettings))
        {
            DataContractSerializer s = new DataContractSerializer(o.GetType());

            s.WriteStartObject(w, o);
            foreach (NamespaceAttribute ns in attributes)                      
                w.WriteAttributeString("xmlns", ns.Prefix, null, ns.Uri);

            // content
            s.WriteObjectContent(w, o);
            s.WriteEndObject(w);
        }
    }
}

Answer 3

我也在努力解决这个问题。我在下面提出的解决方案不是最佳恕我直言，但它的工作原理和上面的Marc Gravell一样，我建议使用XmlSerializer。

诀窍是在类中添加一个返回XmlSerializerNamespaces对象的字段。必须使用XmlNamespaceDeclarations属性修饰此字段。在类的构造函数中，添加名称空间，如下面的示例所示。在下面的xml中注意，根元素以及someString元素都是正确的前缀。

More info on XmlSerializerNamespaces

Schemas reference

[XmlRoot(Namespace="http://STPMonitor.myDomain.com")]
public class CFMessage : IQueueMessage<CFQueueItem>
{
    [XmlNamespaceDeclarations]
    public XmlSerializerNamespaces xmlns;

    [XmlAttribute("schemaLocation", Namespace=System.Xml.Schema.XmlSchema.InstanceNamespace)]
    public string schemaLocation = "http://STPMonitor.myDomain.com/schemas/CFMessage.xsd";

    [XmlAttribute("type")]
    public string Type { get; set; }

    [XmlAttribute("username")]
    public string UserName { get; set; }

    [XmlAttribute("somestring", Namespace = "http://someURI.com")]
    public string SomeString = "Hello World";


    public List<CFQueueItem> QueueItems { get; set; }

    public CFMessage()
    {
        xmlns = new XmlSerializerNamespaces();
        xmlns.Add("myDomain", "http://STPMonitor.myDomain.com");
        xmlns.Add("xyz", "http://someURI.com");
    }
}


<?xml version="1.0" encoding="utf-16"?>
<myDomain:CFMessage xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xyz="http://someURI.com"
xsi:schemaLocation="http://STPMonitor.myDomain.com/schemas/CFMessage.xsd"
xyz:somestring="Hello World" type="JOIN" username="SJ-3-3008-1"
xmlns:myDomain="http://STPMonitor.myDomain.com" />

Answer 4

通过以下方式添加“http://www.w3.org/2001/XMLSchema”命名空间：

    private static string DataContractSerialize(object obj)
    {
        StringWriter sw = new StringWriter();

        DataContractSerializer serializer = new DataContractSerializer(obj.GetType());

        using (XmlTextWriter xw = new XmlTextWriter(sw))
        {
            //serializer.WriteObject(xw, obj);
            //
            // Insert namespace for C# types
            serializer.WriteStartObject(xw, obj);
            xw.WriteAttributeString("xmlns", "x", null, "http://www.w3.org/2001/XMLSchema");
            serializer.WriteObjectContent(xw, obj);
            serializer.WriteEndObject(xw);
        }

        StringBuilder buffer = sw.GetStringBuilder();

        return buffer.ToString();
    }

具有多个命名空间的DataContractSerializer

4 个答案: