Question

我正在使用XmlSerializer创建一个表示XML文件的对象，现在我想在xml文件的rootelement中添加一个schemalocation。我可以添加如下的

命名空间

        XmlSerializer serializer = new XmlSerializer(typeof(MyClass));
        System.IO.FileStream fs = new FileStream(@"C:\test.xml", FileMode.Create);
        TextWriter writer = new StreamWriter(fs, new UTF8Encoding());

        XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
        ns.Add("xy","http://www.w3.org/2005/08/addressing");
        ns.Add("xlink","http://www.w3.org/1999/xlink");
        serializer.Serialize(writer, myObject, ns);

但是如何在我的c＃代码中向我的根元素添加xsi:schemalocation属性。命名空间添加了一个简单的ns.Add()。我想避免搞乱xsd.exe生成的c＃类。或者我是否必须手动编辑生成的c＃类并将一些属性添加到我的xml的根元素中？

编辑：我看过我需要手动编辑c＃的示例，但必须有一种方法可以在代码中执行此操作！如果我们能够将命名空间添加到根元素中，为什么不能添加schemalocations？

Answer 1

XSD.exe生成部分类，因此您可以添加自己的单独部分类来保存xsi：schemaLocation等字段或属性。

因此，添加到@Petru Gardea的示例elementB类，您只需要在项目中创建另一个文件并添加此分部类：

public partial class elementB 
{
    [XmlAttributeAttribute("schemaLocation", Namespace="http://www.w3.org/2001/XMLSchema-instance")]
    public string xsiSchemaLocation = "http://www.acme.com/xml/OrderXML-1-0.xsd";
}

有一个问题我遇到了这样做，默认情况下xsd.exe没有为生成的文件添加命名空间。当您创建自己的此分部类时，它很可能位于命名空间中。由于＆lt; 默认命名空间＆gt;并且显式定义的命名空间不匹配，partial不起作用。因此，您需要在xsd.exe上使用namespace选项来实际将生成的类放入命名空间。

Answer 2

我们假设以下XSD：

<?xml version="1.0" encoding="utf-8" ?>
<!-- XML Schema generated by QTAssistant/XSD Module (http://www.paschidev.com) -->
<xsd:schema targetNamespace="http://tempuri.org/XMLSchema.xsd" xmlns="http://tempuri.org/XMLSchema.xsd" elementFormDefault="qualified" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
    <xsd:element name="elementB">
        <xsd:complexType>
            <xsd:sequence>
                <xsd:element name="FirstName" type="xsd:string"/>
                <xsd:element name="LastName" type="xsd:string"/>
            </xsd:sequence>
        </xsd:complexType>
    </xsd:element>  
</xsd:schema>

至少有两种方法可以做到这一点。第一个依赖于继承以及如何使用序列化器注释。

xsd.exe生成：

//------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated by a tool.
//     Runtime Version:4.0.30319.18034
//
//     Changes to this file may cause incorrect behavior and will be lost if
//     the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

using System.Xml.Serialization;

// 
// This source code was auto-generated by xsd, Version=4.0.30319.1.
// 

/// <remarks/>
[System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "4.0.30319.1")]
[System.SerializableAttribute()]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Xml.Serialization.XmlTypeAttribute(AnonymousType=true, Namespace="http://tempuri.org/XMLSchema.xsd")]
[System.Xml.Serialization.XmlRootAttribute(Namespace="http://tempuri.org/XMLSchema.xsd", IsNullable=false)]
public partial class elementB {

    private string firstNameField;

    private string lastNameField;

    /// <remarks/>
    public string FirstName {
        get {
            return this.firstNameField;
        }
        set {
            this.firstNameField = value;
        }
    }

    /// <remarks/>
    public string LastName {
        get {
            return this.lastNameField;
        }
        set {
            this.lastNameField = value;
        }
    }
}

要“注入”xsi:schemaLocation添加新课程elementA : elementB;注意：

System.Xml.Serialization.XmlRootAttribute setup
schemaLocation属性设置。

测试程序：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml.Serialization;
using System.IO;
using System.Xml;

namespace ConsoleApplication2
{
    class Program
    {
        static void Main(string[] args)
        {
            elementB b = new elementB();
            b.FirstName = "P";
            b.LastName = "G";

            XmlSerializer ser = new XmlSerializer(typeof(elementB));
            StringBuilder sb = new StringBuilder();
            using (XmlWriter writer = XmlWriter.Create(sb, new XmlWriterSettings() { Indent = true })) 
            {
                ser.Serialize(writer, b);
            }
            Console.WriteLine(sb.ToString());

            elementA a = new elementA();
            a.FirstName = "P";
            a.LastName = "G";
            a.schemaLocation = "http://tempuri.org/XMLSchema.xsd me";
            ser = new XmlSerializer(typeof(elementA));
            sb = new StringBuilder();
            using (XmlWriter writer = XmlWriter.Create(sb, new XmlWriterSettings() { Indent = true }))
            {
                ser.Serialize(writer, a);
            }
            Console.WriteLine(sb.ToString());
        }
    }
}

[System.SerializableAttribute()]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true, Namespace = "http://tempuri.org/XMLSchema.xsd")]
[System.Xml.Serialization.XmlRootAttribute(Namespace = "http://tempuri.org/XMLSchema.xsd", ElementName = "elementB", IsNullable = false)]
public partial class elementA : elementB
{

    private string torefField;

    /// <remarks/>
    [System.Xml.Serialization.XmlAttributeAttribute(Form = System.Xml.Schema.XmlSchemaForm.Qualified, Namespace = "http://www.w3.org/2001/XMLSchema-instance")]
    public string schemaLocation
    {
        get
        {
            return this.torefField;
        }
        set
        {
            this.torefField = value;
        }
    }
}

生成预期结果：

<?xml version="1.0" encoding="utf-16"?>
<elementB xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://tempuri.org/XMLSchema.xsd">
  <FirstName>P</FirstName>
  <LastName>G</LastName>
</elementB>
<?xml version="1.0" encoding="utf-16"?>
<elementB xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xsi:schemaLocation="http://tempuri.org/XMLSchema.xsd me" xmlns="http://tempuri.org/XMLSchema.xsd">
  <FirstName>Petru</FirstName>
  <LastName>Gardea</LastName>
</elementB>

第二种方式依赖于一个自定义编写器，它会在你想要的地方注入你想要的东西（假设有适当的逻辑）。

您实现了自定义XmlWriter：

class MyXmlWriter : XmlWriter
{
    XmlWriter _writer;
    bool _docElement = true;

    public string SchemaLocation { get; set; }
    public string NoNamespaceSchemaLocation { get; set; }

    public MyXmlWriter(XmlWriter writer)
    {
        _writer = writer;
    }

    (other methods omitted)

    public override void WriteStartElement(string prefix, string localName, string ns)
    {
        _writer.WriteStartElement(prefix, localName, ns);
        if (_docElement)
        {
            if (!string.IsNullOrEmpty(SchemaLocation))
            {
                _writer.WriteAttributeString("xsi", "schemaLocation", "http://www.w3.org/2001/XMLSchema-instance", SchemaLocation);
            }
            if (!string.IsNullOrEmpty(NoNamespaceSchemaLocation))
            {
                _writer.WriteAttributeString("xsi", "noNamesapceSchemaLocation", "http://www.w3.org/2001/XMLSchema-instance", NoNamespaceSchemaLocation);
            }
            _docElement = false;
        }
    }

    (other methods omitted)

}

修改过的测试程序：

static void Main(string[] args)
{
    elementB b = new elementB();
    b.FirstName = "P";
    b.LastName = "G";

    XmlSerializer ser = new XmlSerializer(typeof(elementB));
    StringBuilder sb = new StringBuilder();
    using (XmlWriter writer = XmlWriter.Create(sb, new XmlWriterSettings() { Indent = true })) 
    {
        ser.Serialize(writer, b);
    }
    Console.WriteLine(sb.ToString());

    sb = new StringBuilder();

    using (XmlWriter writer = XmlWriter.Create(sb, new XmlWriterSettings() { Indent = true }))
    {
        MyXmlWriter newWriter = new MyXmlWriter(writer) { SchemaLocation = "http://tempuri.org/XMLSchema.xsd me" };
        ser.Serialize(newWriter, b);
    }
    Console.WriteLine(sb.ToString());
}

结果是一样的......

<?xml version="1.0" encoding="utf-16"?>
<elementB xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://tempuri.org/XMLSchema.xsd">
  <FirstName>P</FirstName>
  <LastName>G</LastName>
</elementB>
<?xml version="1.0" encoding="utf-16"?>
<elementB xsi:schemaLocation="http://tempuri.org/XMLSchema.xsd me" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://tempuri.org/XMLSchema.xsd">
  <FirstName>P</FirstName>
  <LastName>G</LastName>
</elementB>

如何将xsi schemalocation添加到root c＃object XmlSerializer

2 个答案: