如何将 XML 文档映射到 entity framework 对象？

Question

我有以下 entity framework 对象：

namespace Proj.Accounting.Entity
{
    using System;
    using System.Collections.Generic;
    using System.Xml.Serialization;

    public partial class DocumentStatus
    {
        public DocumentStatus()
        {
            this.Documents = new HashSet<Document>();
            this.DocumentsTrackings = new HashSet<DocumentsTracking>();
            this.DocumentsTrackingChildDocuments = new HashSet<DocumentsTrackingChildDocument>();
        }
        [XmlElement("StateId")]
        public int StateId { get; set; }
        [XmlElement("StateName")]
        public string StateName { get; set; }
        [XmlElement("GroupId")]
        public Nullable<int> GroupId { get; set; }

        public virtual ICollection<Document> Documents { get; set; }
        public virtual ICollection<DocumentsTracking> DocumentsTrackings { get; set; }
        public virtual ICollection<DocumentsTrackingChildDocument> DocumentsTrackingChildDocuments { get; set; }
    }
}

我按照 class 将实体映射到 xml 字段（不是那样工作的）：

using System;
using System.Collections;
using System.IO;
using System.Xml.Serialization;

namespace Proj.Accounting.Data
{
    class XMLObjects
    {
        public static T ConvertXmlToClass<T>(string xml)
        {
            var serializer = new XmlSerializer(typeof(T));
            return (T)serializer.Deserialize(new StringReader(xml));
        }
    }
}

以及我用来映射数据的方法：

private void button1_Click(object sender, EventArgs e)
{
    string xml = "";
    xml +=  "<?xml version=\"1.0\" encoding=\"UTF - 8\"?>";
    xml +=  "<root>";
    xml += " <success>true</success>";
    xml +=  " <data>";
    xml += " <item>";
    xml += " <StateId>0</StateId>";
    xml += " <StateName>Шаблон</StateName>";
    xml += " <GroupId>0</GroupId>";
    xml += " </item>";
    xml +=  "</root>";
    DocumentStatus documentStatus = new DocumentStatus();
    documentStatus = XMLObjects.ConvertXmlToClass<DocumentStatus>(xml);
    int a = 0;
}

我遇到以下异常

System.InvalidOperationException was unhandled   HResult=-2146233079  
 Message=There was an error reflecting type 'Proj.Accounting.Entity.DocumentStatus'. Source=System.Xml  
 StackTrace:
        at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
        at System.Xml.Serialization.XmlReflectionImporter.ImportElement(TypeModel model, XmlRootAttribute root, String defaultNamespace, RecursionLimiter limiter)
        at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(Type type, XmlRootAttribute root, String defaultNamespace)
        at System.Xml.Serialization.XmlSerializer..ctor(Type type, String defaultNamespace)
        at System.Xml.Serialization.XmlSerializer..ctor(Type type)
        at Proj.Accounting.Data.XMLObjects.ConvertXmlToClass[T](String xml) in c:\Users\username\Dropbox\Dev\Proj.Accounting\Proj.Accounting.Data\XMLObjects.cs:line 12
        at Proj.Accounting.Data.MainForm.button1_Click(Object sender, EventArgs e) in c:\Users\username\Dropbox\Dev\Proj.Accounting\Proj.Accounting.Data\MainForm.cs:line 36
        at System.Windows.Forms.Control.OnClick(EventArgs e)
        at System.Windows.Forms.Button.OnClick(EventArgs e)
        at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
        at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
        at System.Windows.Forms.Control.WndProc(Message& m)
        at System.Windows.Forms.ButtonBase.WndProc(Message& m)
        at System.Windows.Forms.Button.WndProc(Message& m)
        at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message&m)
        at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
        at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
        at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
        at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
        at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
        at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
        at System.Windows.Forms.Application.Run(Form mainForm)
        at Proj.Accounting.Data.Program.Main() in c:\Users\username\Dropbox\Dev\Proj.Accounting\Proj.Accounting.Data\Program.cs:line 19
        at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
        at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
        at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
        at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
        at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
        at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
        at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
        at System.Threading.ThreadHelper.ThreadStart()   InnerException: System.InvalidOperationException HResult=-2146233079
        Message=Cannot serialize member 'Proj.Accounting.Entity.DocumentStatus.Documents' of type 'System.Collections.Generic.ICollection`1[[Proj.Accounting.Entity.Document,
 Proj.Accounting.Entity, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]', see inner exception for more details.
        Source=System.Xml
        StackTrace:
             at System.Xml.Serialization.StructModel.CheckSupportedMember(TypeDesc typeDesc, MemberInfo member, Type type)
             at System.Xml.Serialization.StructModel.GetPropertyModel(PropertyInfo propertyInfo)
             at System.Xml.Serialization.StructModel.GetFieldModel(MemberInfo memberInfo)
             at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
             at System.Xml.Serialization.XmlReflectionImporter.ImportStructLikeMapping(StructModel model, String ns, Boolean openModel, XmlAttributes a, RecursionLimiter limiter)
             at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
        InnerException: System.NotSupportedException
             HResult=-2146233067
             Message=Cannot serialize member Proj.Accounting.Entity.DocumentStatus.Documents of type
 System.Collections.Generic.ICollection`1[[Proj.Accounting.Entity.Document,
 Proj.Accounting.Entity, Version=1.0.0.0, Culture=neutral,
 PublicKeyToken=null]] because it is an interface.
             InnerException:

Answer 1

可序列化

我认为问题在于您的 class 文档不可序列化。当您序列化一个对象时，它们的所有字段也必须是可序列化的。如果不想序列化Documents成员，就用[System.Xml.Serialization.XmlIgnoreAttribute]

标记

要将对象序列化为 XML，请使用序列化方法，反序列化请使用反序列化方法。你不需要更多。

更多信息：https://msdn.microsoft.com/es-es/library/system.xml.serialization.xmlserializer(v=vs.110).aspx

小贴士

此外，将您的字符串连接更改为使用 StringBuilder。如果这是测试代码，请记住您可以在字符串上使用 += 运算符，这会产生 Clean Code。

示例：

string xml = "";
xml = xml + "<?xml version=\"1.0\" encoding=\"UTF - 8\"?>";
xml = xml + "<root>";

使用 += 运算符（结果相同但更清晰）

string xml = "";
xml += "<?xml version=\"1.0\" encoding=\"UTF - 8\"?>";
xml += "<root>";

使用 StringBuilder（最好最快的方法）

StringBuilder xml = new StringBuilder();
xml.Append("<?xml version=\"1.0\" encoding=\"UTF - 8\"?>");
xml.Append("<root>");

Answer 2

一切尽在 :

Cannot serialize member Proj.Accounting.Entity.DocumentStatus.Documents of type
System.Collections.Generic.ICollection1[[Proj.Accounting.Entity.Document, Proj.Accounting.Entity, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]] because it is an interface

接口不可序列化。将所有 ICollection 属性转换为类型 HashSet 以启用这些项目的序列化。

如何将 XML 文档映射到 entity framework 对象？

How to map XML document to entity framework object?

.net

c#

entity-framework

xml-serialization

entity-framework-6