blocks|key|1139763|text|查看msdn中的这个link，这里有一个序列化单例的例子。反序列化后，您应该返回引用，而不是对象。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1139764|entityMap|0|LINK|mutability|MUTABLE|url|http://msdn.microsoft.com/en-us/library/system.runtime.serialization.iserializable.aspx^0|A|4|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

Check this <a href="http://msdn.microsoft.com/en-us/library/system.runtime.serialization.iserializable.aspx" rel="nofollow">link</a> from msdn, there is an example on serializing a singleton. After deserialization you should return the reference and not the object.

blocks|key|1133936|text|尝试使用NetDataContractSerializer-|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1133937|NetDataContractSerializer与DataContractSerializer的一个重要区别在于:+NetDataContractSerializer在序列化后的|1133938|中包含CLR类型信息，而DataContractSerializer则不包含。因此，只有当序列化和反序列化端共享相同的NetDataContractSerializer类型时，才能使用CLR。|blockquote|1133939|1133940|序列化程序可以序列化已应用DataContractAttribute或SerializableAttribute属性的类型。它还序列化实现ISerializable的类型。|1133941|1133942|代码示例：|1133943|[DataContract(Name+=+"Customer",+Namespace+=+"http://www.contoso.com")]
class+Person+:+IExtensibleDataObject
{
++++[DataMember()]
++++public+string+FirstName;
++++[DataMember]
++++public+string+LastName;
++++[DataMember()]
++++public+int+ID;

++++public+Person(string+newfName,+string+newLName,+int+newID)
++++{
++++++++FirstName+=+newfName;
++++++++LastName+=+newLName;
++++++++ID+=+newID;
++++}

++++private+ExtensionDataObject+extensionData_Value;++++
++++public+ExtensionDataObject+ExtensionData
++++{
++++++++get+{+return+extensionData_Value;+}
++++++++set+{+extensionData_Value+=+value;+}
++++}
}|code-block|syntax|javascript|1133944|本地化：|1133945|Person+p1+=+new+Person("Zighetti",+"Barbara",+101);
FileStream+fs+=+new+FileStream(fileName,+FileMode.Create);
XmlDictionaryWriter+writer+=+XmlDictionaryWriter.CreateTextWriter(fs);
NetDataContractSerializer+ser+=+new+NetDataContractSerializer();
ser.WriteObject(writer,+p1);|1133946|Msdn+Link+here|offset|length|1133947|entityMap|0|LINK|mutability|MUTABLE|url|http://msdn.microsoft.com/en-us/library/system.runtime.serialization.netdatacontractserializer.aspx^0|0|0|0|0|0|0|0|0|0|0|0|E|0|0^^$0|@$1|2|3|4|5|6|7|17|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|18|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|19|8|@]|9|@]|A|$]]|$1|G|3|-4|5|6|7|1A|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|1B|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|1C|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|1D|8|@]|9|@]|A|$]]|$1|M|3|N|5|O|7|1E|8|@]|9|@]|A|$P|Q]]|$1|R|3|S|5|6|7|1F|8|@]|9|@]|A|$]]|$1|T|3|U|5|O|7|1G|8|@]|9|@]|A|$P|Q]]|$1|V|3|W|5|6|7|1H|8|@]|9|@$X|1I|Y|1J|1|1K]]|A|$]]|$1|Z|3|-4|5|6|7|1L|8|@]|9|@]|A|$]]]|10|$11|$5|12|13|14|A|$15|16]]]]

Try using NetDataContractSerializer-

<blockquote>
 The NetDataContractSerializer differs from the DataContractSerializer
 in one important way: the NetDataContractSerializer includes CLR type
 information in the serialized XML, whereas the DataContractSerializer
 does not. Therefore, the NetDataContractSerializer can be used only if
 both the serializing and deserializing ends share the same CLR types. 
 
 The serializer can serialize types to which either the
 DataContractAttribute or SerializableAttribute attribute has been
 applied. It also serializes types that implement ISerializable.
</blockquote>

Code example:

<pre><code>[DataContract(Name = "Customer", Namespace = "http://www.contoso.com")]
class Person : IExtensibleDataObject
{
 [DataMember()]
 public string FirstName;
 [DataMember]
 public string LastName;
 [DataMember()]
 public int ID;

 public Person(string newfName, string newLName, int newID)
 {
 FirstName = newfName;
 LastName = newLName;
 ID = newID;
 }

 private ExtensionDataObject extensionData_Value; 
 public ExtensionDataObject ExtensionData
 {
 get { return extensionData_Value; }
 set { extensionData_Value = value; }
 }
}
</code></pre>

Searialization:

<pre><code>Person p1 = new Person("Zighetti", "Barbara", 101);
FileStream fs = new FileStream(fileName, FileMode.Create);
XmlDictionaryWriter writer = XmlDictionaryWriter.CreateTextWriter(fs);
NetDataContractSerializer ser = new NetDataContractSerializer();
ser.WriteObject(writer, p1);
</code></pre>

<a href="http://msdn.microsoft.com/en-us/library/system.runtime.serialization.netdatacontractserializer.aspx" rel="nofollow">Msdn Link here</a>

blocks|key|1133962|text|(+.net+4.0的代码)|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1133963|我遇到了同样的问题:反序列化需要创建单例类的一个新实例，它可以(！)这样做是因为它在一个成员函数中:构造函数对成员是可见的，但该实例不能替换从外部可见的单例实例(+"this")。|1133964|因此，您必须将属性从反序列化实例复制到"this“实例中。|1133965|手工复制很快就过时了，所以这里是我的解决方案，使用反射复制未标记为xmlignore的公共可写成员|1133966|++++public+static+class+SerializationHelpers
++++{

++++++///+<summary>
++++++///+Copy+all+public+props+and+fields+that+are+not+xmlignore
++++++///+</summary>
++++++///+<typeparam+name="T"></typeparam>
++++++///+<param+name="target"></param>
++++++///+<param+name="other"></param>
++++++public+static+void+CopyTypeFields<T>(T+target,+T+other)
++++++{

++++++++//+get+all+public+static+properties+of+MyClass+type
++++++++PropertyInfo[]+propertyInfos+=+other.GetType().GetProperties(BindingFlags.Public++

++++++++%7C+BindingFlags.Instance);
++++++++FieldInfo[]+fis+=+other.GetType().GetFields(BindingFlags.Public+%7C+
++++++++BindingFlags.Instance);


++++++++foreach+(FieldInfo+fi+in+fis)
++++++++{
++++++++++if+((fi.Attributes+&+FieldAttributes.FieldAccessMask)+!=+
++++++++++++++FieldAttributes.Literal+&&
++++++++++++++(fi.Attributes+&+FieldAttributes.FieldAccessMask)+!=+
++++++++++++++FieldAttributes.Static)
++++++++++{
++++++++++++if+(IsXmlIgnored(fi))+{+continue;+}
++++++++++++var+myval+=+fi.GetValue(other);
++++++++++++fi.SetValue(target,+myval);
++++++++++}
++++++++}


++++++++foreach+(PropertyInfo+pi+in+propertyInfos)
++++++++{
++++++++++if+(!pi.CanWrite+%7C%7C+!pi.CanRead)+{+continue;+}
++++++++++if+(IsXmlIgnored(pi))+{+continue;+}

++++++++++var+myval+=+pi.GetValue(other,+null);
++++++++++pi.SetValue(target,+myval,+null);
++++++++}
++++++}

++++++private+static+bool+IsXmlIgnored(MemberInfo+pi)
++++++{
++++++++object[]+fiGetCustomAttributes+=+pi.GetCustomAttributes(false);
++++++++foreach+(object+ob+in+fiGetCustomAttributes)
++++++++{
++++++++++if+(ob.GetType().
++++++++++++++Equals(typeof(System.Xml.Serialization.XmlIgnoreAttribute)))
++++++++++{
++++++++++++return+true;
++++++++++}
++++++++}
++++++++return+false;
++++++}

++++}

++++//+to+use+it+...
++++//+the+deserialization+method+of+the+singleton+mySingleton



++++public+bool+loadSingleton()
++++{
++++++bool+ret=+false;

++++++try
++++++{
++++++++Type+myType+=+GetType();
++++++++XmlSerializer+reader+=+new+XmlSerializer(myType);
++++++++try
++++++++{
++++++++++using+(StreamReader+file+=+new+StreamReader(filename))
++++++++++{
++++++++++++try
++++++++++++{
++++++++++++++mySingleton+t1+=+(mySingleton)reader.Deserialize(file);
++++++++++++++CopySerializationFields(t1);
++++++++++++++ret=+true;
++++++++++++}

++++++++++++catch
++++++++++++{
++++++++++++++...
++++++++++++}
++++++++++}
++++++++}
++++++++catch
++++++++{
++++++++++...
++++++++}
++++++}
++++++catch+(Exception+ex)
++++++{
++++++++...
++++++}
++++++return+ret;
++++}


++++private+void+CopySerializationFields(ProcessingSettings+other)
++++{
++++++SerializationHelpers.CopyTypeFields(this,+other);
++++}|code-block|syntax|javascript|1133967|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|Q|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|R|8|@]|9|@]|A|$]]|$1|H|3|I|5|J|7|S|8|@]|9|@]|A|$K|L]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

(code for .net 4.0)

I had the same problem: 
the de-serialization needs to create a new instance of the singleton class, which it can(!) do because its inside a member function: the constructor is visible to members, but that instance cannot replace the singleton instance visible from the outside (the "this").

So you have to copy the properties from your de-serialized instance into the "this" instance.

Doing the copying by hand gets old fast, so here is my solution using reflection to copy the public writable members that are not marked [xmlignore]:

<pre><code> public static class SerializationHelpers
 {

 /// &lt;summary&gt;
 /// Copy all public props and fields that are not xmlignore
 /// &lt;/summary&gt;
 /// &lt;typeparam name="T"&gt;&lt;/typeparam&gt;
 /// &lt;param name="target"&gt;&lt;/param&gt;
 /// &lt;param name="other"&gt;&lt;/param&gt;
 public static void CopyTypeFields&lt;T&gt;(T target, T other)
 {

 // get all public static properties of MyClass type
 PropertyInfo[] propertyInfos = other.GetType().GetProperties(BindingFlags.Public 

 | BindingFlags.Instance);
 FieldInfo[] fis = other.GetType().GetFields(BindingFlags.Public | 
 BindingFlags.Instance);


 foreach (FieldInfo fi in fis)
 {
 if ((fi.Attributes &amp; FieldAttributes.FieldAccessMask) != 
 FieldAttributes.Literal &amp;&amp;
 (fi.Attributes &amp; FieldAttributes.FieldAccessMask) != 
 FieldAttributes.Static)
 {
 if (IsXmlIgnored(fi)) { continue; }
 var myval = fi.GetValue(other);
 fi.SetValue(target, myval);
 }
 }


 foreach (PropertyInfo pi in propertyInfos)
 {
 if (!pi.CanWrite || !pi.CanRead) { continue; }
 if (IsXmlIgnored(pi)) { continue; }

 var myval = pi.GetValue(other, null);
 pi.SetValue(target, myval, null);
 }
 }

 private static bool IsXmlIgnored(MemberInfo pi)
 {
 object[] fiGetCustomAttributes = pi.GetCustomAttributes(false);
 foreach (object ob in fiGetCustomAttributes)
 {
 if (ob.GetType().
 Equals(typeof(System.Xml.Serialization.XmlIgnoreAttribute)))
 {
 return true;
 }
 }
 return false;
 }

 }

 // to use it ...
 // the deserialization method of the singleton mySingleton



 public bool loadSingleton()
 {
 bool ret= false;

 try
 {
 Type myType = GetType();
 XmlSerializer reader = new XmlSerializer(myType);
 try
 {
 using (StreamReader file = new StreamReader(filename))
 {
 try
 {
 mySingleton t1 = (mySingleton)reader.Deserialize(file);
 CopySerializationFields(t1);
 ret= true;
 }

 catch
 {
 ...
 }
 }
 }
 catch
 {
 ...
 }
 }
 catch (Exception ex)
 {
 ...
 }
 return ret;
 }


 private void CopySerializationFields(ProcessingSettings other)
 {
 SerializationHelpers.CopyTypeFields(this, other);
 }
</code></pre>

blocks|key|4860865|text|我刚刚搜索了很长时间来寻找类似的原子类解决方案，并找到了Marc+Gravell的answer+to+a+similar+problem。这也适用于单例。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|4860866|在单例类中，实现由接口System.Runtime.Serialization.IObjectReference.定义的GetRealObject方法如果需要，您还可以将以前序列化的数据添加到单例中，并将静态引用作为反序列化后使用的引用返回。|4860867|下面是我的例子：|4860868|[System.Runtime.Serialization.DataContract]
public+class+MySingletonClass+:+System.Runtime.Serialization.IObjectReference
{
++++private+MySingletonClass()
++++{
++++}

++++private+static+MySingletonClass+_Instance;
++++public+static+MySingletonClass+Instance
++++{
++++++++get
++++++++{
++++++++++++if+(_Instance+==+null)
++++++++++++++++_Instance+=+new+MySingletonClass();
++++++++++++return+_Instance;
++++++++}
++++}

++++object+System.Runtime.Serialization.IObjectReference.GetRealObject(System.Runtime.Serialization.StreamingContext+context)
++++{
++++++++MySingletonClass+realObject+=+Instance;
++++++++realObject.Merge(this);
++++++++return+realObject;
++++}

++++private+void+Merge(MySingletonClass+otherInstance)
++++{
++++++++//+do+your+merging+here
++++}
}|code-block|syntax|javascript|4860869|您也可以将其用于原子类。您只需将实例属性更改为GetInstance方法，并在GetRealObject方法中使用适当的属性(即ID)调用它。|4860870|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/users/23354/marc-gravell|1|https://stackoverflow.com/a/1990054/1706067^0|S|C|0|15|R|1|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@$A|Z|B|10|1|11]|$A|12|B|13|1|14]]|C|$]]|$1|D|3|E|5|6|7|15|8|@]|9|@]|C|$]]|$1|F|3|G|5|6|7|16|8|@]|9|@]|C|$]]|$1|H|3|I|5|J|7|17|8|@]|9|@]|C|$K|L]]|$1|M|3|N|5|6|7|18|8|@]|9|@]|C|$]]|$1|O|3|-4|5|6|7|19|8|@]|9|@]|C|$]]]|P|$Q|$5|R|S|T|C|$U|V]]|W|$5|R|S|T|C|$U|X]]]]

I just searched quite long for a similar solution for atomic classes and have found an <a href="https://stackoverflow.com/a/1990054/1706067">answer to a similar problem</a> by <a href="https://stackoverflow.com/users/23354/marc-gravell">Marc Gravell</a>. This also works for singletons.

In your singleton class you implement the GetRealObject method defined by the interface System.Runtime.Serialization.IObjectReference. There you could also add previously serialized data to the singleton if needed and return the static reference as the reference that is used after deserialization.

Here's my example:

<pre><code>[System.Runtime.Serialization.DataContract]
public class MySingletonClass : System.Runtime.Serialization.IObjectReference
{
 private MySingletonClass()
 {
 }

 private static MySingletonClass _Instance;
 public static MySingletonClass Instance
 {
 get
 {
 if (_Instance == null)
 _Instance = new MySingletonClass();
 return _Instance;
 }
 }

 object System.Runtime.Serialization.IObjectReference.GetRealObject(System.Runtime.Serialization.StreamingContext context)
 {
 MySingletonClass realObject = Instance;
 realObject.Merge(this);
 return realObject;
 }

 private void Merge(MySingletonClass otherInstance)
 {
 // do your merging here
 }
}
</code></pre>

You can use this for atomic classes too. You only have to change the Instance property to a GetInstance method and call it with the appropriate property in the GetRealObject method (i.e. an ID).

blocks|key|1139796|text|[DataContract]
public+sealed+class+SerializableSingletonPattern
{
++++public+static+SerializableSingletonPattern+Instance+{+get;+private+set;+}+=+new+SerializableSingletonPattern();
++++[DataMember]+public+bool+YourData+{+get;+private+set;+}

++++//+explicit+static+constructor+so+C#+compiler+will+not+mark+type+as+beforefieldinit
++++static+SerializableSingletonPattern()+{+}

++++SerializableSingletonPattern()+//+your+constructor
++++{
++++}

++++[OnDeserialized]
++++void+OnDeserialized(StreamingContext+context)
++++{
++++++++Instance+=+this;
++++}
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1139797|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>[DataContract]
public sealed class SerializableSingletonPattern
{
 public static SerializableSingletonPattern Instance { get; private set; } = new SerializableSingletonPattern();
 [DataMember] public bool YourData { get; private set; }

 // explicit static constructor so C# compiler will not mark type as beforefieldinit
 static SerializableSingletonPattern() { }

 SerializableSingletonPattern() // your constructor
 {
 }

 [OnDeserialized]
 void OnDeserialized(StreamingContext context)
 {
 Instance = this;
 }
}
</code></pre>

I've problems to serialize and deserialize a singleton via DataContract.

First some facts:

<pre><code>1.) Singleton is "internal"
2.) Singleton contains Dictionaries
</code></pre>

My serialization and deserialization works fine, but it isn't the right way for a singleton. If I deserialize the xml, I always generate a new instance of my singleton and overwrite the current reference of the singleton object - but after this it isn't a singleton further.

Has anybody any idea? - Thanks.

Serialize Singleton via DataContract

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我在通过DataContract序列化和反序列化单例时遇到了问题。首先是一些事实：1.) Singleton is "internal"2.) Singleton contains Dictionaries我的序列化和反序列化工作得很好，但这不是单例的正确方式。如果我反序列化xml，我总是生成一个单例的新实例，并覆盖单...

问通过DataContract序列化单例
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