c# - DataContractJsonSerializer 生成哈希列表而不是哈希

Question

我希望有一个 Dictionary 对象的形式:

var dict = new Dictionary<string,string>()
{
    {"blah", "bob"},
    {"blahagain", "bob"}
};

以以下形式序列化成JSON:

{ "blah": "bob", "blahagain": "bob" }

不

[ { "key": "blah", "value": "bob" }, { "key": "blahagain", "value": "bob"}]

为什么看起来是一种怪异的序列化集合的通用尝试？

DataContractJsonSerializer使用ISerializable接口(interface)来产生这个东西。在我看来，好像有人从 ISerializable 中获取了 XML 输出并从中删除了这个东西。

这里有办法覆盖.Net 使用的默认序列化吗？我可以只从 Dictionary 派生并覆盖序列化方法吗？

张贴以听取人们可能有的任何警告或建议。

Answer 1

好吧，我决定回避 Dictionary 对象的 DataContract 序列化。

我在我的根对象中创建了两个虚拟方法。

public virtual void prepareForSerialization();
public virtual void postDeserialize();

然后为我的类的每个字典属性指定字符串 DataMember 类属性。字符串被序列化，字典不再直接序列化。

[DataMember]
public string dictionaryString;
public Dictionary<int, string> dict;

然后，当我的代码调用序列化时，它还会首先调用 prepareForSerialization。

public override void prepareForSerialization() { 
    base.prepareForSerialization();
}

public override void postDeSerialize() {
    base.postDeSerialize();
}

具有 Dictionary 成员的派生类将调用我自己的 Dictionary 序列化器。

注意:这是一个适合我目的的简单序列化。 YMMV。Javascript 将功劳归功于另一篇 stackoverfow 帖子。忘记是哪一个了。

/// <summary>
/// Extension methods needed to implement Javascript dates for C#
/// </summary>
public static class MyExtensions{
    public static double JavascriptTicks(this DateTime dt) {
        DateTime d1 = new DateTime(1970, 1, 1);
        DateTime d2 = dt.ToUniversalTime();
        TimeSpan ts = new TimeSpan(d2.Ticks - d1.Ticks);
        return ts.TotalMilliseconds;
    }        
}
/// <summary>
/// Serialize a single value
/// </summary>
/// <param name="o">An object to serialize</param>
/// <returns>A JSON string of the value</returns>
if (o is string) {
    return string.Format("\"{0}\"", o);
} else if (o is DateTime) {
    return string.Format("new Date({0})", ((DateTime)o).JavascriptTicks()); ;
} else if(o.GetType().IsValueType) {
    return o.ToString();
} else {
    //Here you want a check of the form if is IMySerializer, then call your prepare before
    //using the .Net one.
    DataContractJsonSerializer json = new DataContractJsonSerializer(o.GetType());
    using(MemoryStream ms = new MemoryStream())
    using (StreamReader sr = new StreamReader(ms)) {
        json.WriteObject(ms, o);
        ms.Position = 0;
        return sr.ReadToEnd();
    }
}

/// <summary>
/// Serializes a List object into JSON
/// </summary>
/// <param name="list">The IList interface into the List</param>
/// <returns>A JSON string of the list</returns>
public string SerializeList(IList list) {
    string result = null;
    if (list != null) {
        IEnumerator it = list.GetEnumerator();
        StringBuilder sb = new StringBuilder();
        long len = list.Count;
        sb.Append("[");
        while (it.MoveNext()) {
            if (it.Current is IList) {
                sb.Append(SerializeList((IList)it.Current));
            } else if (it.Current is IDictionary) {
                sb.Append(SerializeDictionary((IDictionary)it.Current));
            } else {
                sb.Append(SerializeValue(it.Current));
            }
            --len;
            if (len > 0) sb.Append(",");
        }
        sb.Append("]");
        result = sb.ToString();
    }
    return result;
}
/// <summary>
/// Returns a stringified key of the object
/// </summary>
/// <param name="o">The key value</param>
/// <returns></returns>
public string SerializeKey(object o) {
    return string.Format("\"{0}\"", o); 
}
/// <summary>
/// Serializes a dictionary into JSON
/// </summary>
/// <param name="dict">The IDictionary interface into the Dictionary</param>
/// <returns>A JSON string of the Dictionary</returns>
public string SerializeDictionary(IDictionary dict) {
    string result = null;
    if (dict != null) {
        IDictionaryEnumerator it = dict.GetEnumerator();
        StringBuilder sb = new StringBuilder();
        long len = dict.Count;
        sb.Append("{");
        while (it.MoveNext()) {
            sb.Append(SerializeKey(it.Key));
            sb.Append(":");
            if (it.Value is IList) {
                sb.Append(SerializeList((IList)it.Value));
            } else if (it.Value is IDictionary) {
                sb.Append(SerializeDictionary((IDictionary)it.Value));
            } else {
                sb.Append(SerializeValue(it.Value));
            }
            --len;
            if (len > 0) sb.Append(",");
        }
        sb.Append("}");
        result = sb.ToString();
    }
    return result;
}