使用 DataContactSerializer 反序列化 xml Dictionary<TKey,TValue>

Question

我正在尝试使用 DataContractSerializer 反序列化 Dictionary<TKey,TValue>。我没有例外，我的字典回来了null。我已经阅读了多篇文章，尝试了多种实现，但仍然没有成功。我敢肯定，我错过了一些非常小的东西，并且真的可以用几双眼睛为我查看它，也许将它分开并告诉我我的问题出在哪里。任何帮助是极大的赞赏。我使用的类如下：

[DataContract]
public class Config
{
    public Config()
    {
        SerializableDictionary = new SerializableDictionary<int, string>();
    }

    [DataMember]
    public SerializableDictionary<int, string> SerializableDictionary { get; set; }
}

[CollectionDataContract(Name = "SerializableDictionary", ItemName = "DictionaryItem", KeyName = "Key", ValueName = "Value")]
public sealed class SerializableDictionary<TKey, TValue> : Dictionary<TKey, TValue>
{

}

我的 XML：

<?xml version="1.0" encoding="utf-8"?>
<Config xmlns="http://TestNameSpace" >
  <SerializableDictionary >
    <DictionaryItem>
      <Key>1</Key>
      <Value>one</Value>
    </DictionaryItem>
    <DictionaryItem>
      <Key>2</Key>
      <Value>two</Value>
    </DictionaryItem>
    <DictionaryItem>
      <Key>3</Key>
      <Value>three</Value>
    </DictionaryItem>
    <DictionaryItem>
      <Key>4</Key>
      <Value>four</Value>
    </DictionaryItem>
    <DictionaryItem>
      <Key>5</Key>
      <Value>five</Value>
    </DictionaryItem>
    <DictionaryItem>
      <Key>6</Key>
      <Value>six</Value>
    </DictionaryItem>
  </SerializableDictionary>
</Config>

调用方法：

private static void Main(string[] args)
{
    Config config = null;
    using (var stream = new FileStream(
        Path.GetDirectoryName(
            Assembly.GetExecutingAssembly()
                    .Location) + "\\Dictionary.xml", FileMode.Open))
    using (var reader = XmlDictionaryReader.CreateTextReader(stream, new XmlDictionaryReaderQuotas()))
    {
        var serializer = new DataContractSerializer(typeof(Config), "Config", "http://TestNameSpace");

        config = (Config)serializer.ReadObject(reader);
    }

    foreach (var obj in config.SerializableDictionary)
        Console.WriteLine(obj.Value);

}

Answer 1

为了弄清楚这一点，我创建了一个 Encode 方法，该方法使用您为 Config 类创建的相同 DataContract 进行编码。

public static void Encode()
{
  var path = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location) + "\\dataOut.xml";
  using (var stream = new FileStream(path, FileMode.OpenOrCreate))
  {
    var serializer = new DataContractSerializer(typeof(Config), "Config", "http://TestNameSpace");

    serializer.WriteObject(stream, new Config(){SerializableDictionary = new SerializableDictionary<int, string> { { 1, "hello" }, { 2, "world"} }});
  }
}

查看输出后，很明显问题是子类型的命名空间问题。

<Config xmlns="http://TestNameSpace" xmlns:a="http://schemas.datacontract.org/2004/07/DeserializeDictionary" xmlns:i="http://www.w3.org/2001/XMLSchema-instance">
  <a:SerializableDictionary>
    <a:DictionaryItem>
      <a:Key>1</a:Key>
      <a:Value>hello</a:Value>
    </a:DictionaryItem>
    <a:DictionaryItem>
      <a:Key>2</a:Key>
      <a:Value>world</a:Value>
    </a:DictionaryItem>
  </a:SerializableDictionary>
</Config>

我首先将Namespace = "http://TestNameSpace" 添加到SerializableDictionary 的CollectionDataContract，但这并没有解决它。只有在我也将Namespace = "http://TestNameSpace" 添加到 Config 的 DataContract 之后，它才会序列化您创建 XML 文件的方式。

这里是更新后的 Config 和 SerializableDictionary 让它为我工作：

[DataContract(Namespace = "http://TestNameSpace")]
public class Config
{
  public Config()
  {
    SerializableDictionary = new SerializableDictionary<int, string>();
  }

  [DataMember]
  public SerializableDictionary<int, string> SerializableDictionary { get; set; }
}

[CollectionDataContract(Name = "SerializableDictionary", ItemName = "DictionaryItem", KeyName = "Key", ValueName = "Value", Namespace = "http://TestNameSpace")]
public sealed class SerializableDictionary<TKey, TValue> : Dictionary<TKey, TValue>
{

}