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.NET中是否有可序列化的通用键/值对类?

我正在寻找一个可以包含在Web服务中的键/值对对象。

我尝试使用.NET的 System.Collections.Generic.KeyValuePair<> class,但它没有在Web服务中正确序列化。在Web服务中,Key和Value属性未被序列化,使得此类无用,除非有人知道解决此问题的方法。

是否有其他可用于此情况的泛型类?

我使用.NET的 System.Web.UI.Pair class,但它使用Object作为其类型。如果仅用于类型安全,那么使用Generic类会很好。

75
Dan Herbert

只需定义一个struct/class。

[Serializable]
public struct KeyValuePair<K,V>
{
  public K Key {get;set;}
  public V Value {get;set;}
}
90
leppie

我不认为Dictionary<>本身不是XML可序列化的,当我需要通过Web服务发送字典对象时,我最终自己包装了Dictionary<>对象并添加了对IXMLSerializable的支持。

/// <summary>
/// Represents an XML serializable collection of keys and values.
/// </summary>
/// <typeparam name="TKey">The type of the keys in the dictionary.</typeparam>
/// <typeparam name="TValue">The type of the values in the dictionary.</typeparam>
[XmlRoot("dictionary")]
public class SerializableDictionary<TKey, TValue> : Dictionary<TKey, TValue>, IXmlSerializable
{
    #region Constants

    /// <summary>
    /// The default XML tag name for an item.
    /// </summary>
    private const string DEFAULT_ITEM_TAG = "Item";

    /// <summary>
    /// The default XML tag name for a key.
    /// </summary>
    private const string DEFAULT_KEY_TAG = "Key";

    /// <summary>
    /// The default XML tag name for a value.
    /// </summary>
    private const string DEFAULT_VALUE_TAG = "Value";

    #endregion

    #region Protected Properties

    /// <summary>
    /// Gets the XML tag name for an item.
    /// </summary>
    protected virtual string ItemTagName
    {
        get
        {
            return DEFAULT_ITEM_TAG;
        }
    }

    /// <summary>
    /// Gets the XML tag name for a key.
    /// </summary>
    protected virtual string KeyTagName
    {
        get
        {
            return DEFAULT_KEY_TAG;
        }
    }

    /// <summary>
    /// Gets the XML tag name for a value.
    /// </summary>
    protected virtual string ValueTagName
    {
        get
        {
            return DEFAULT_VALUE_TAG;
        }
    }

    #endregion

    #region Public Methods

    /// <summary>
    /// Gets the XML schema for the XML serialization.
    /// </summary>
    /// <returns>An XML schema for the serialized object.</returns>
    public XmlSchema GetSchema()
    {
        return null;
    }

    /// <summary>
    /// Deserializes the object from XML.
    /// </summary>
    /// <param name="reader">The XML representation of the object.</param>
    public void ReadXml(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 != XmlNodeType.EndElement)
        {
            reader.ReadStartElement(ItemTagName);

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

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

            this.Add(key, value);

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

        reader.ReadEndElement();
    }

    /// <summary>
    /// Serializes this instance to XML.
    /// </summary>
    /// <param name="writer">The writer to serialize to.</param>
    public void WriteXml(XmlWriter writer)
    {
        XmlSerializer keySerializer = new XmlSerializer(typeof(TKey));
        XmlSerializer valueSerializer = new XmlSerializer(typeof(TValue));

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

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

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

            writer.WriteEndElement();
        }
    }

    #endregion
}
22
Compile This

您将找到KeyValuePairs无法在此处序列化的原因 MSDN博客文章

Struct答案是最简单的解决方案,但不是唯一的解决方案。一个“更好”的解决方案是编写一个Serializable的Custom KeyValurPair类。

17
user56931
 [Serializable]
 public class SerializableKeyValuePair<TKey, TValue>
    {

        public SerializableKeyValuePair()
        {
        }

        public SerializableKeyValuePair(TKey key, TValue value)
        {
            Key = key;
            Value = value;
        }

        public TKey Key { get; set; }
        public TValue Value { get; set; }

    }
6
GregoryBrad

在4.0 Framework中,还添加了可序列化且可等同的Tuple类。您可以使用Tuple.Create(a, b)new Tuple<T1, T2>(a, b)

1
Peter Oehlert

使用DataContractSerializer,因为它可以处理键值对。

    public static string GetXMLStringFromDataContract(object contractEntity)
    {
        using (System.IO.MemoryStream writer = new System.IO.MemoryStream())
        {
            var dataContractSerializer = new DataContractSerializer(contractEntity.GetType());
            dataContractSerializer.WriteObject(writer, contractEntity);
            writer.Position = 0;
            var streamReader = new System.IO.StreamReader(writer);
            return streamReader.ReadToEnd();
        }
    }
0
Hasse

KeyedCollection是一种字典,可以直接序列化为xml而不会产生任何废话。唯一的问题是你必须通过以下方式访问值:coll [“key”]。

0
Will

DataTable是我最喜欢的(仅)包装要序列化为JSON的数据的集合,因为它很容易扩展而不需要额外的struct并且像Tuple<>[]的可序列化替换一样

也许不是最干净的方式,但我更喜欢直接在类中包含和使用它(应该序列化),而不是声明一个新的struct

class AnyClassToBeSerialized
{
    public DataTable KeyValuePairs { get; }

    public AnyClassToBeSerialized
    {
        KeyValuePairs = new DataTable();
        KeyValuePairs.Columns.Add("Key", typeof(string));
        KeyValuePairs.Columns.Add("Value", typeof(string));
    }

    public void AddEntry(string key, string value)
    {
        DataRow row = KeyValuePairs.NewRow();
        row["Key"] = key; // "Key" & "Value" used only for example
        row["Value"] = value;
        KeyValuePairs.Rows.Add(row);
    }
}
0
Teodor Tite

XmlSerializer不适用于字典。哦,KeyValuePairs也有问题

http://www.codeproject.com/Tips/314447/XmlSerializer-doesnt-work-with-Dictionaries-Oh-and

0
Akodo_Shado