如何从不使用XElement的自定义XML序列化/反序列化为`Dictionary <int,string =“”>`?</int,>

时间:2012-09-23 16:48:28

标签: c# .net xml mono

Dictionary<int, string>如何使用XML中的键和值填充它,如

<items>
<item id='int_goes_here' value='string_goes_here'/>
</items>

并将其序列化为不使用XElement的XML?

10 个答案:

答案 0 :(得分:96)

借助临时item班级

public class item
{
    [XmlAttribute]
    public int id;
    [XmlAttribute]
    public string value;
}

示例词典:

Dictionary<int, string> dict = new Dictionary<int, string>()
{
    {1,"one"}, {2,"two"}
};

XmlSerializer serializer = new XmlSerializer(typeof(item[]), 
                                 new XmlRootAttribute() { ElementName = "items" });

<强>序列化

serializer.Serialize(stream, 
              dict.Select(kv=>new item(){id = kv.Key,value=kv.Value}).ToArray() );

<强>反序列化

var orgDict = ((item[])serializer.Deserialize(stream))
               .ToDictionary(i => i.id, i => i.value);

----------------------------------------------- -------------------------------

如果您改变主意,以下是如何使用XElement 完成的。

<强>序列化

XElement xElem = new XElement(
                    "items",
                    dict.Select(x => new XElement("item",new XAttribute("id", x.Key),new XAttribute("value", x.Value)))
                 );
var xml = xElem.ToString(); //xElem.Save(...);

<强>反序列化

XElement xElem2 = XElement.Parse(xml); //XElement.Load(...)
var newDict = xElem2.Descendants("item")
                    .ToDictionary(x => (int)x.Attribute("id"), x => (string)x.Attribute("value"));

答案 1 :(得分:28)

Paul Welter的ASP.NET blog有一个可序列化的字典。但它不使用属性。我将在代码下面解释原因。

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

[XmlRoot("dictionary")]
public class SerializableDictionary<TKey, TValue>
    : Dictionary<TKey, TValue>, IXmlSerializable
{
    #region IXmlSerializable Members
    public System.Xml.Schema.XmlSchema GetSchema()
    {
        return null;
    }

    public void ReadXml(System.Xml.XmlReader reader)
    {
        XmlSerializer keySerializer = new XmlSerializer(typeof(TKey));
        XmlSerializer valueSerializer = new XmlSerializer(typeof(TValue));

        bool wasEmpty = reader.IsEmptyElement;
        reader.Read();

        if (wasEmpty)
            return;

        while (reader.NodeType != System.Xml.XmlNodeType.EndElement)
        {
            reader.ReadStartElement("item");

            reader.ReadStartElement("key");
            TKey key = (TKey)keySerializer.Deserialize(reader);
            reader.ReadEndElement();

            reader.ReadStartElement("value");
            TValue value = (TValue)valueSerializer.Deserialize(reader);
            reader.ReadEndElement();

            this.Add(key, value);

            reader.ReadEndElement();
            reader.MoveToContent();
        }
        reader.ReadEndElement();
    }

    public void WriteXml(System.Xml.XmlWriter writer)
    {
        XmlSerializer keySerializer = new XmlSerializer(typeof(TKey));
        XmlSerializer valueSerializer = new XmlSerializer(typeof(TValue));

        foreach (TKey key in this.Keys)
        {
            writer.WriteStartElement("item");

            writer.WriteStartElement("key");
            keySerializer.Serialize(writer, key);
            writer.WriteEndElement();

            writer.WriteStartElement("value");
            TValue value = this[key];
            valueSerializer.Serialize(writer, value);
            writer.WriteEndElement();

            writer.WriteEndElement();
        }
    }
    #endregion
}

首先,这个代码有一个问题。假设您从其他来源读取字典:

<dictionary>
  <item>
    <key>
      <string>key1</string>
    </key>
    <value>
      <string>value1</string>
    </value>
  </item>
  <item>
    <key>
      <string>key1</string>
    </key>
    <value>
      <string>value2</string>
    </value>
  </item>
</dictionary>

这将在de-seariazation上抛出异常,因为你只能有一个字典的密钥。


您必须在序列化词典中使用XElement的原因是词典未定义为Dictionary<String,String>,词典为Dictionary<TKey,TValue>

要查看问题,请问自己:让我们说我们有一个TValue序列化到使用Elements的东西,它将自己描述为XML(比如词典Dictionary<int,Dictionary<int,string>>(不是那个)不常见的模式,它是一个查找表)),你的仅属性版本如何完全代表一个属性内的字典?

答案 2 :(得分:6)

默认情况下,字典在C#中不是Serializable,我不知道为什么,但它似乎是一个设计选择。

现在,我建议使用Json.NET将其转换为JSON并从那里转换为字典(反之亦然)。除非你真的需要XML,否则我建议你完全使用JSON。

答案 3 :(得分:3)

基于L.B.的答案。

用法:

var serializer = new DictionarySerializer<string, string>();
serializer.Serialize("dictionary.xml", _dictionary);
_dictionary = _titleDictSerializer.Deserialize("dictionary.xml");

通用类:

public class DictionarySerializer<TKey, TValue>
{
    [XmlType(TypeName = "Item")]
    public class Item
    {
        [XmlAttribute("key")]
        public TKey Key;
        [XmlAttribute("value")]
        public TValue Value;
    }

    private XmlSerializer _serializer = new XmlSerializer(typeof(Item[]), new XmlRootAttribute("Dictionary"));

    public Dictionary<TKey, TValue> Deserialize(string filename)
    {
        using (FileStream stream = new FileStream(filename, FileMode.Open))
        using (XmlReader reader = XmlReader.Create(stream))
        {
            return ((Item[])_serializer.Deserialize(reader)).ToDictionary(p => p.Key, p => p.Value);
        }
    }

    public void Serialize(string filename, Dictionary<TKey, TValue> dictionary)
    {
        using (var writer = new StreamWriter(filename))
        {
            _serializer.Serialize(writer, dictionary.Select(p => new Item() { Key = p.Key, Value = p.Value }).ToArray());
        }
    }
}

答案 4 :(得分:3)

我有一个结构KeyValuePairSerializable

[Serializable]
public struct KeyValuePairSerializable<K, V>
{
    public KeyValuePairSerializable(KeyValuePair<K, V> pair)
    {
        Key = pair.Key;
        Value = pair.Value;
    }

    [XmlAttribute]
    public K Key { get; set; }

    [XmlText]
    public V Value { get; set; }

    public override string ToString()
    {
        return "[" + StringHelper.ToString(Key, "") + ", " + StringHelper.ToString(Value, "") + "]";
    }
}

然后,Dictionary属性的XML序列化由:

[XmlIgnore]
public Dictionary<string, string> Parameters { get; set; }

[XmlArray("Parameters")]
[XmlArrayItem("Pair")]
[DebuggerBrowsable(DebuggerBrowsableState.Never)] // not necessary
public KeyValuePairSerializable<string, string>[] ParametersXml
{
    get 
    { 
        return Parameters?.Select(p => new KeyValuePairSerializable<string, string>(p)).ToArray(); 
    }
    set
    {
        Parameters = value?.ToDictionary(i => i.Key, i => i.Value);
    }
}

该属性必须是数组,而不是List。

答案 5 :(得分:2)

编写一个类A,它包含一个B类数组.B类应该有一个id属性和一个value属性。将xml反序列化为类A.将A中的数组转换为所需的字典。

要序列化字典,请将其转换为A类实例,并序列化...

答案 6 :(得分:2)

您可以使用ExtendedXmlSerializer。 如果你有一个班级:

public class TestClass
{
    public Dictionary<int, string> Dictionary { get; set; }
}

并创建此类的实例:

var obj = new TestClass
{
    Dictionary = new Dictionary<int, string>
    {
        {1, "First"},
        {2, "Second"},
        {3, "Other"},
    }
};

您可以使用ExtendedXmlSerializer序列化此对象:

var serializer = new ConfigurationContainer()
    .UseOptimizedNamespaces() //If you want to have all namespaces in root element
    .Create();

var xml = serializer.Serialize(
    new XmlWriterSettings { Indent = true }, //If you want to formated xml
    obj);

输出xml如下所示:

<?xml version="1.0" encoding="utf-8"?>
<TestClass xmlns:sys="https://extendedxmlserializer.github.io/system" xmlns:exs="https://extendedxmlserializer.github.io/v2" xmlns="clr-namespace:ExtendedXmlSerializer.Samples;assembly=ExtendedXmlSerializer.Samples">
  <Dictionary>
    <sys:Item>
      <Key>1</Key>
      <Value>First</Value>
    </sys:Item>
    <sys:Item>
      <Key>2</Key>
      <Value>Second</Value>
    </sys:Item>
    <sys:Item>
      <Key>3</Key>
      <Value>Other</Value>
    </sys:Item>
  </Dictionary>
</TestClass>

您可以从nuget安装ExtendedXmlSerializer或运行以下命令:

Install-Package ExtendedXmlSerializer

答案 7 :(得分:2)

KeyedCollection的工作方式类似于字典,并且可以序列化。

首先创建一个包含键和值的类:

/// <summary>
/// simple class
/// </summary>
/// <remarks></remarks>
[Serializable()]
public class cCulture
{
    /// <summary>
    /// culture
    /// </summary>
    public string culture;

    /// <summary>
    /// word list
    /// </summary>
    public List<string> list;

    /// <summary>
    /// status
    /// </summary>
    public string status;
}

然后创建KeyedCollection类型的类,并将该类的属性定义为键。

/// <summary>
/// keyed collection.
/// </summary>
/// <remarks></remarks>
[Serializable()]
public class cCultures : System.Collections.ObjectModel.KeyedCollection<string, cCulture>
{
    protected override string GetKeyForItem(cCulture item)
    {
        return item.culture;
    }
}

使用full来序列化此类数据。

答案 8 :(得分:1)

我使用可序列化的类来进行不同模块之间的WCF通信。 下面是一个可序列化类的示例,它也用作DataContract。 我的方法是使用LINQ的强大功能将Dictionary转换为开箱即用的可序列化List&lt;&gt; KeyValuePair&lt;&gt;:

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Runtime.Serialization;
    using System.Xml.Serialization;

    namespace MyFirm.Common.Data
    {
        [DataContract]
        [Serializable]
        public class SerializableClassX
        {
            // since the Dictionary<> class is not serializable,
            // we convert it to the List<KeyValuePair<>>
            [XmlIgnore]
            public Dictionary<string, int> DictionaryX 
            {
                get
                {
                    return  SerializableList == null ? 
                            null :
                            SerializableList.ToDictionary(item => item.Key, item => item.Value);
                }

                set
                {
                    SerializableList =  value == null ?
                                        null :
                                        value.ToList();
                }
            }

            [DataMember]
            [XmlArray("SerializableList")]
            [XmlArrayItem("Pair")]
            public List<KeyValuePair<string, int>> SerializableList { get; set; }
        }
    }

用法很简单 - 我将字典分配给我的数据对象的字典字段 - DictionaryX。 SerializableClassX内部通过将分配的字典转换为可序列化的List&lt;&gt;来支持序列化。 KeyValuePair&lt;&gt;:

    // create my data object
    SerializableClassX SerializableObj = new SerializableClassX(param);

    // this will call the DictionaryX.set and convert the '
    // new Dictionary into SerializableList
    SerializableObj.DictionaryX = new Dictionary<string, int>
    {
        {"Key1", 1},
        {"Key2", 2},
    };

答案 9 :(得分:0)

Sharpeserializer(开源)有一个简单的方法:

http://www.sharpserializer.com/

它可以直接序列化/反序列化字典。

无需使用任何属性标记对象,也不必在Serialize方法中提供对象类型(请参阅here)。

通过nuget安装:Install-package sharpserializer

然后很简单:

Hello World (来自官方网站):

// create fake obj
var obj = createFakeObject();

// create instance of sharpSerializer
// with standard constructor it serializes to xml
var serializer = new SharpSerializer();

// serialize
serializer.Serialize(obj, "test.xml");

// deserialize
var obj2 = serializer.Deserialize("test.xml");