ServiceStack ormlite json不会从数据库反序列化

Question

ServiceStack ORMLite不会从Postgresql反序列化我的类。

将对象保留在高速缓存中可以解决问题，但是无法将它们重新加载（可以保存）。

下面是重现该问题的代码。

void Main()
{
    var inv = new Inventory();
    inv.Items.Add(new Item{Id=1,CreatedAt=DateTime.Now, Key="potion10", Descriptions=new Dictionary<int, string>{{1,"Poção que recupera um pouco de vida."},{2,"Potion that restores a little of health."}}, HealthModifier=10,IsUseable=true, Names=new Dictionary<int, string>{{1,"Poção Leve"},{2,"Minor Potion"}}, UpdatedAt=DateTime.Now}, 2);

    var invJson = inv.ToJson().To<Inventory>(); // can't deserialize
    var invJsv = inv.ToJsv().To<Inventory>(); // same problem
}

public class Item
{
    public Item()
    {
        Names = new Dictionary<int, string>();
        Descriptions = new Dictionary<int, string>();
    }

    public long Id { get; set; }

    public string Key { get; set; }

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

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

    public int HealthModifier { get; set; }

    public bool IsUseable { get; set; }

    public DateTime CreatedAt { get; set; }

    public DateTime UpdatedAt { get; set; }
}

public class Inventory
{
    public Inventory()
    {
        Items = new Dictionary<Item, int>();
    }

    public Dictionary<Item, int> Items { get; set; }
}

Postgresql上的JSON与上面的代码相同。

{
    "Items":{
        "{"Id":1,
        "Key":"potion10",
        "Names":{
            "1":"Poção Leve",
            "2":"Minor Potion"
        },
        "Descriptions":{
            "1":"Poção que recupera um pouco de vida.",
            "2":"Potion that restores a little of health."
        },
        "HealthModifier":10,
        "IsUseable":true,
        "CreatedAt":"\/Date(1430743156138-0300)\/",
        "UpdatedAt":"\/Date(1430743156139-0300)\/"
    }:2
}
}

Answer 1

问题是您的班级“ Inventory有一个由复杂班级键入的字典：

public Dictionary<Item, int> Items { get; set; }

但是，根据ServiceStack.Text文档

任何IDictionary都序列化为标准JSON对象，即：

  {"A":1,"B":2,"C":3,"D":4} 

不幸的是，您的Item类不能表示为简单的字符串，因此不能用作JSON属性名称 。

您可以做的是将项序列化为键值对数组。 由于ServiceStack文本序列化程序支持[DataMember]别名 ，还支持忽略数据成员 ，因此您可以执行以下操作：

[DataContract]
public class Inventory
{
    public Inventory()
    {
        Items = new Dictionary<Item, int>();
    }

    [IgnoreDataMember]
    public Dictionary<Item, int> Items { get; set; }

    [DataMember(Name = "Items")]
    public KeyValuePair<Item, int> [] ItemArray
    {
        get
        {
            return Items == null ? null : Items.ToArray();
        }
        set
        {
            (Items ?? (Items = new Dictionary<Item, int>())).Clear();
            if (value != null)
                foreach (var pair in value)
                    Items[pair.Key] = pair.Value;
        }
    }
}

这将对有效的JSON进行序列化和反序列化，如下所示：

 { "Items": [ { "Key": { "Id": 1, "Key": "potion10", "Names": { "1": "Poção Leve", "2": "Minor Potion" }, "Descriptions": { "1": "Poção que recupera um pouco de vida.", "2": "Potion that restores a little of health." }, "HealthModifier": 10, "IsUseable": true, "CreatedAt": "2015-05-04T02:07:10.7216263-04:00", "UpdatedAt": "2015-05-04T02:07:10.7216263-04:00" }, "Value": 2 } ] } 

但是，您提到您的JSON来自Postgresql。 JSON是什么样的？ 您可能需要根据实际收到的内容调整序列化或类。