如何反序列化JSON自定義類型

Question

我有以下的JSON：

{ 
    "ExitCode": 1, 
    "ErrorMessage": "", 
    "NumberOfMatches": 9, 
    "NumberOfExtractFrames": 3, 
    "ProcessingTime": 111, 
    "MatchResult": [ 
    { 
     "TopLeft": "2, 8", 
     "BottomRight": "377, 157", 
     "Confidence": 1.0, 
     "HighConfidenceLevel": true, 
     "SearchFrame": "77, 69, 36, 26", 
    }, 
    { 
     "TopLeft": "2, 169", 
     "BottomRight": "377, 318", 
     "Confidence": 0.99999982118606567, 
     "HighConfidenceLevel": true, 
     "SearchFrame": "77, 230, 36, 26", 
    }, 
... 

和創建的類：

public class JsonParse 
{ 
    public int ExitCode { get; set; } 
    public string ErrorMessage { get; set; } 
    public int NumberOfMatches { get; set; } 
    public int NumberOfExtractFrames { get; set; } 
    public int ProcessingTime { get; set; } 

    public List<MatchResult> MatchResult { get; set; } 

} 

public class MatchResult 
{ 
    public Coordinate TopLeft { get; set; } 
    public Coordinate BottomRight { get; set; } 
    public decimal Confidence { get; set; } 
    public bool HighConfidenceLevel { get; set; } 
    //public Tuple<int, int, int, int> SearchFrame { get; set; } 
} 

public class Coordinate 
{ 
    public int X { get; set; } 
    public int Y { get; set; } 
} 

當然

，它崩潰當我嘗試這樣做：

_jsonParse = JsonConvert.DeserializeObject<JsonParse>(jsonParseString); 

我嘗試創建一個轉換器：

public class CoordinateConverter : CustomCreationConverter<Coordinate> 
{ 
    public override Coordinate Create(Type objectType) 
    { 
     return new Coordinate(); 
    } 
} 

和

_jsonParse = JsonConvert.DeserializeObject<JsonParse>(jsonParseString, new CoordinateConverter()); 

這是行不通的。如何正確聲明和使用轉換器？

Answer 1

我使用這個類爲我的所有對象：

public class JsonConverter 
{ 
    public static string ObjectToString(object o) 
    { 
     var javaScriptSerializer = new JavaScriptSerializer(); 
     string jsonString = javaScriptSerializer.Serialize(o); 

     return jsonString; 
    } 

    public static object StringToObject(string data) 
    { 
     var json_serializer = new JavaScriptSerializer(); 
     return json_serializer.DeserializeObject(data); 
    } 
} 

要使用它：

Coordinate co = new Coordinate(){ X=10,Y=20 } 
string json = JsonConverter.ObjectToString(co); 
Coordinate coParsed = (Coordinate)StringToObject(json); 

，包括

Namespace: System.Web.Script.Serialization 

並添加引用過

Assembly: System.Web.Extensions (in System.Web.Extensions.dll) 

在這個例子中，你可以將它用於任何類型的對象我使用了座標，因爲我可以簡單地聲明它。

Answer 2

我做它來創建以下轉換器：

public class CoordinateConverter : CustomCreationConverter<Coordinate> 
{ 
    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer) 
    { 
     var values = reader.Value.ToString().Split(',').Select(n => Convert.ToInt32(n)).ToArray(); 
     Coordinate coordinates = new Coordinate() { X = values[0], Y = values[1] }; 
     return coordinates; 
    } 

    public override bool CanConvert(Type objectType) 
    { 
     if (objectType == typeof(Coordinate)) 
     { 
      return true; 
     } 

     return false; 
    } 

    public override Coordinate Create(Type objectType) 
    { 
     return new Coordinate(); 
    } 
}