C# 我可以用Json.net在一次操作中将嵌套属性序列化到类中吗?
假设我有一个这样的模型:C# 我可以用Json.net在一次操作中将嵌套属性序列化到类中吗?,c#,multithreading,json.net,C#,Multithreading,Json.net,假设我有一个这样的模型: public class MyModel { public string Name { get; set; } public string[] Size { get; set; } public string Weight { get; set; } } 像这样: { "name" : "widget", "details" : { "size" : [ "XL","M","S",
public class MyModel
{
public string Name { get; set; }
public string[] Size { get; set; }
public string Weight { get; set; }
}
像这样:
{
"name" : "widget",
"details" : {
"size" : [
"XL","M","S",
]
"weight" : "heavy"
}
}
public class MyModel
{
[JsonProperty("name")]
public string Name { get; set; }
public Details details { get; set; }
[JsonIgnore]
public string[] Size
{
get
{
return details != null ? details.size : null;
}
set
{
if (details == null)
{
details = new Details();
}
details.size = value;
}
}
[JsonIgnore]
public string Weight
{
get
{
return details != null ? details.weight : null;
}
set
{
if (details == null)
{
details = new Details();
}
details.weight = value;
}
}
}
var deserializedModel = JsonConvert.DeserializeObject<MyModel>("your json string...");
var myModel = new MyModel { Name = "widget", Size = new[] { "XL", "M", "S" }, Weight = "heavy" };
string serializedObject = JsonConvert.SerializeObject(myModel);
[JsonConverter(typeof(MyModelConverter))]
public class MyModel
{
[JsonProperty("name")]
public string Name { get; set; }
[JsonProperty("size")]
public string[] Size { get; set; }
[JsonProperty("weight")]
public string Weight { get; set; }
}
public class TestClass
{
public static void Test()
{
string json = @"{
""name"" : ""widget"",
""details"" : {
""size"" : [
""XL"",""M"",""S"",
],
""weight"" : ""heavy""
}
}";
var mod = JsonConvert.DeserializeObject<MyModel>(json);
Debug.WriteLine(JsonConvert.SerializeObject(mod, Formatting.Indented));
}
}
我一直在试图找到一种方法来序列化我的对象,而不需要为“名称”和“细节”创建一个模型,因为这不能很好地映射到我的数据库,所以需要进行一些处理来填充类
我可以在JsonConvert.PopulateObject()上进行多次传递,如下所示:
但在我的真实代码中,我运行多个线程,PopulateObject不是线程安全的,它会阻塞应用程序。PopulateJsonAsync()的注释表示不要使用它,而是在PopulateObject()上使用Task.Run()
这不起作用,在我调用应用程序时仍会锁定它,如:
await Task.Run(() => JsonConvert.PopulateObject(response.ToString(), productDetail));
if (response["results"].HasValues)
{
await Task.Run(() => JsonConvert.PopulateObject(response["results"][0].ToString(), productDetail));
}
一些人通过了,但最终应用程序完全被线程锁定。如果我删除PopulateObject,所有线程都会很好地终止,所以我很确定这个函数不是线程安全的
是否有一种简洁的线程安全方法可以在一个步骤中填充我的对象 这应该有效:
public class MyModelJsonConverter : JsonConverter
{
public override bool CanRead
{
get { return true; }
}
public override bool CanConvert(Type objectType)
{
return objectType == typeof(MyModel);
}
public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
{
if (objectType != typeof(MyModel))
{
throw new ArgumentException("objectType");
}
switch (reader.TokenType)
{
case JsonToken.Null:
{
return null;
}
case JsonToken.StartObject:
{
reader.Read();
break;
}
default:
{
throw new JsonSerializationException();
}
}
var result = new MyModel();
bool inDetails = false;
while (reader.TokenType == JsonToken.PropertyName)
{
string propertyName = reader.Value.ToString();
if (string.Equals("name", propertyName, StringComparison.OrdinalIgnoreCase))
{
reader.Read();
result.Name = serializer.Deserialize<string>(reader);
}
else if (string.Equals("size", propertyName, StringComparison.OrdinalIgnoreCase))
{
if (!inDetails)
{
throw new JsonSerializationException();
}
reader.Read();
result.Size = serializer.Deserialize<string[]>(reader);
}
else if (string.Equals("weight", propertyName, StringComparison.OrdinalIgnoreCase))
{
if (!inDetails)
{
throw new JsonSerializationException();
}
reader.Read();
result.Weight = serializer.Deserialize<string>(reader);
}
else if (string.Equals("details", propertyName, StringComparison.OrdinalIgnoreCase))
{
reader.Read();
if (reader.TokenType != JsonToken.StartObject)
{
throw new JsonSerializationException();
}
inDetails = true;
}
else
{
reader.Skip();
}
reader.Read();
}
if (inDetails)
{
if (reader.TokenType != JsonToken.EndObject)
{
throw new JsonSerializationException();
}
reader.Read();
}
return result;
}
public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
{
if (value == null)
{
writer.WriteNull();
return;
}
var model = value as MyModel;
if (model == null) throw new JsonSerializationException();
writer.WriteStartObject();
writer.WritePropertyName("name");
writer.WriteValue(model.Name);
writer.WritePropertyName("details");
writer.WriteStartObject();
writer.WritePropertyName("size");
serializer.Serialize(writer, model.Size);
writer.WritePropertyName("weight");
writer.WriteValue(model.Weight);
writer.WriteEndObject();
writer.WriteEndObject();
}
}
[JsonConverter(typeof(MyModelJsonConverter))]
public class MyModel
{
public string Name { get; set; }
public string[] Size { get; set; }
public string Weight { get; set; }
}
公共类MyModelJsonConverter:JsonConverter
{
公共覆盖布尔可读取
{
获取{return true;}
}
公共覆盖布尔CanConvert(类型objectType)
{
返回objectType==typeof(MyModel);
}
公共重写对象ReadJson(JsonReader阅读器,类型objectType,对象existingValue,JsonSerializer序列化程序)
{
if(objectType!=typeof(MyModel))
{
抛出新ArgumentException(“objectType”);
}
开关(reader.TokenType)
{
案例JsonToken.Null:
{
返回null;
}
案例JsonToken.StartObject:
{
reader.Read();
打破
}
违约:
{
抛出新的JsonSerializationException();
}
}
var结果=新的MyModel();
bool inDetails=false;
while(reader.TokenType==JsonToken.PropertyName)
{
string propertyName=reader.Value.ToString();
if(string.Equals(“name”、propertyName、StringComparison.OrdinalIgnoreCase))
{
reader.Read();
result.Name=serializer.Deserialize(读取器);
}
else if(string.Equals(“size”、propertyName、StringComparison.OrdinalIgnoreCase))
{
如果(!inDetails)
{
抛出新的JsonSerializationException();
}
reader.Read();
result.Size=serializer.Deserialize(读取器);
}
else if(string.Equals(“weight”、propertyName、StringComparison.OrdinalIgnoreCase))
{
如果(!inDetails)
{
抛出新的JsonSerializationException();
}
reader.Read();
result.Weight=序列化程序.反序列化(读取器);
}
else if(string.Equals(“详细信息”、propertyName、StringComparison.OrdinalIgnoreCase))
{
reader.Read();
if(reader.TokenType!=JsonToken.StartObject)
{
抛出新的JsonSerializationException();
}
inDetails=真;
}
其他的
{
reader.Skip();
}
reader.Read();
}
如果(详细信息)
{
if(reader.TokenType!=JsonToken.EndObject)
{
抛出新的JsonSerializationException();
}
reader.Read();
}
返回结果;
}
公共重写void WriteJson(JsonWriter编写器、对象值、JsonSerializer序列化器)
{
如果(值==null)
{
WriteNull();
返回;
}
var模型=作为MyModel的值;
如果(model==null)抛出新的JsonSerializationException();
writer.WriteStartObject();
writer.WritePropertyName(“名称”);
writer.WriteValue(model.Name);
writer.WritePropertyName(“详细信息”);
writer.WriteStartObject();
writer.WritePropertyName(“大小”);
serializer.Serialize(writer、model.Size);
writer.WritePropertyName(“重量”);
writer.WriteValue(型号、重量);
writer.WriteEndObject();
writer.WriteEndObject();
}
}
[JsonConverter(类型(MyModelJsonConverter))]
公共类MyModel
{
公共字符串名称{get;set;}
公共字符串[]大小{get;set;}
公共字符串权重{get;set;}
}
通过类上的属性,使用它非常简单:
var model = new MyModel
{
Name = "widget",
Size = new[] { "XL", "M", "S" },
Weight = "heavy"
};
string output = JsonConvert.SerializeObject(model);
// {"name":"widget","details":{"size":["XL","M","S"],"weight":"heavy"}}
var model2 = JsonConvert.DeserializeObject<MyModel>(output);
/*
{
Name = "widget",
Size = [ "XL", "M", "S" ],
Weight = "heavy"
}
*/
var模型=新的MyModel
{
Name=“widget”,
大小=新[]{“XL”、“M”、“S”},
重量=“重”
};
字符串输出=JsonConvert.SerializeObject(模型);
//{“name”:“widget”,“details”:{“size”:[“XL”,“M”,“S”],“weight”:“heavy”}
var model2=JsonConvert.DeserializeObject(输出);
/*
{
Name=“widget”,
尺寸=[“XL”、“M”、“S”],
重量=“重”
}
*/
您只需在模型中为详细信息使用一个额外字段,并使用JsonIgnore
属性忽略大小
和重量
字段的序列化即可。因此,您的模型将如下所示:
{
"name" : "widget",
"details" : {
"size" : [
"XL","M","S",
]
"weight" : "heavy"
}
}
public class MyModel
{
[JsonProperty("name")]
public string Name { get; set; }
public Details details { get; set; }
[JsonIgnore]
public string[] Size
{
get
{
return details != null ? details.size : null;
}
set
{
if (details == null)
{
details = new Details();
}
details.size = value;
}
}
[JsonIgnore]
public string Weight
{
get
{
return details != null ? details.weight : null;
}
set
{
if (details == null)
{
details = new Details();
}
details.weight = value;
}
}
}
var deserializedModel = JsonConvert.DeserializeObject<MyModel>("your json string...");
var myModel = new MyModel { Name = "widget", Size = new[] { "XL", "M", "S" }, Weight = "heavy" };
string serializedObject = JsonConvert.SerializeObject(myModel);
[JsonConverter(typeof(MyModelConverter))]
public class MyModel
{
[JsonProperty("name")]
public string Name { get; set; }
[JsonProperty("size")]
public string[] Size { get; set; }
[JsonProperty("weight")]
public string Weight { get; set; }
}
public class TestClass
{
public static void Test()
{
string json = @"{
""name"" : ""widget"",
""details"" : {
""size"" : [
""XL"",""M"",""S"",
],
""weight"" : ""heavy""
}
}";
var mod = JsonConvert.DeserializeObject<MyModel>(json);
Debug.WriteLine(JsonConvert.SerializeObject(mod, Formatting.Indented));
}
}
然后,您可以像这样简单地序列化/反序列化您的模型:
{
"name" : "widget",
"details" : {
"size" : [
"XL","M","S",
]
"weight" : "heavy"
}
}
public class MyModel
{
[JsonProperty("name")]
public string Name { get; set; }
public Details details { get; set; }
[JsonIgnore]
public string[] Size
{
get
{
return details != null ? details.size : null;
}
set
{
if (details == null)
{
details = new Details();
}
details.size = value;
}
}
[JsonIgnore]
public string Weight
{
get
{
return details != null ? details.weight : null;
}
set
{
if (details == null)
{
details = new Details();
}
details.weight = value;
}
}
}
var deserializedModel = JsonConvert.DeserializeObject<MyModel>("your json string...");
var myModel = new MyModel { Name = "widget", Size = new[] { "XL", "M", "S" }, Weight = "heavy" };
string serializedObject = JsonConvert.SerializeObject(myModel);
[JsonConverter(typeof(MyModelConverter))]
public class MyModel
{
[JsonProperty("name")]
public string Name { get; set; }
[JsonProperty("size")]
public string[] Size { get; set; }
[JsonProperty("weight")]
public string Weight { get; set; }
}
public class TestClass
{
public static void Test()
{
string json = @"{
""name"" : ""widget"",
""details"" : {
""size"" : [
""XL"",""M"",""S"",
],
""weight"" : ""heavy""
}
}";
var mod = JsonConvert.DeserializeObject<MyModel>(json);
Debug.WriteLine(JsonConvert.SerializeObject(mod, Formatting.Indented));
}
}
var deserializedModel=JsonConvert.DeserializeObject(“您的json字符串…”);
var myModel=newmymodel{Name=“widget”,Size=new[]{“XL”、“M”、“S”},Weight=“heavy”};
string serializedObject=JsonConvert.SerializeObject(myModel);
您可以使用以下转换器执行此操作:
public class MyModelConverter : JsonConverter
{
[ThreadStatic]
static bool cannotWrite;
// Disables the converter in a thread-safe manner.
bool CannotWrite { get { return cannotWrite; } set { cannotWrite = value; } }
public override bool CanWrite { get { return !CannotWrite; } }
public override bool CanConvert(Type objectType)
{
return typeof(MyModel).IsAssignableFrom(objectType);
}
public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
{
var obj = JObject.Load(reader);
obj.SelectToken("details.size").MoveTo(obj);
obj.SelectToken("details.weight").MoveTo(obj);
using (reader = obj.CreateReader())
{
// Using "populate" avoids infinite recursion.
existingValue = (existingValue ?? new MyModel());
serializer.Populate(reader, existingValue);
}
return existingValue;
}
public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
{
// Disabling writing prevents infinite recursion.
using (new PushValue<bool>(true, () => CannotWrite, val => CannotWrite = val))
{
var obj = JObject.FromObject(value, serializer);
var details = new JObject();
obj.Add("details", details);
obj["size"].MoveTo(details);
obj["weight"].MoveTo(details);
obj.WriteTo(writer);
}
}
}
public static class JsonExtensions
{
public static void MoveTo(this JToken token, JObject newParent)
{
if (newParent == null)
throw new ArgumentNullException();
if (token != null)
{
if (token is JProperty)
{
token.Remove();
newParent.Add(token);
}
else if (token.Parent is JProperty)
{
token.Parent.Remove();
newParent.Add(token.Parent);
}
else
{
throw new InvalidOperationException();
}
}
}
}
public struct PushValue<T> : IDisposable
{
Action<T> setValue;
T oldValue;
public PushValue(T value, Func<T> getValue, Action<T> setValue)
{
if (getValue == null || setValue == null)
throw new ArgumentNullException();
this.setValue = setValue;
this.oldValue = getValue();
setValue(value);
}
#region IDisposable Members
// By using a disposable struct we avoid the overhead of allocating and freeing an instance of a finalizable class.
public void Dispose()
{
if (setValue != null)
setValue(oldValue);
}
#endregion
}
公共类MyModelConverter:JsonConverter
{
[线程静态]
静态布尔不能写;
//以线程安全的方式禁用转换器。
bool CannotWrite{get{return CannotWrite;}set{CannotWrite=value;}
公共重写bool CanWrite{get{return!cannotwrite