我正在使用JSON.NET通过反射将某些数据解析为某些特定属性。
property.SetValue(comInstance, field.Value);
此行它抛出ArgumentException
:
[mscorlib.dll中发生了'System.ArgumentException'类型的未处理异常]
附加信息:'Newtonsoft.Json.Linq.JObject'类型的对象不能转换为'Microsoft.Xna.Framework.Vector2'类型。
我知道这与JsonConverter
类型的Vector2
有一定关系,看起来像这样:
public class Vector2Converter : JsonConverter
{
public override bool CanConvert(Type objectType)
{
return (objectType == typeof(Vector2));
}
public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
{
JObject jsonObject = JObject.Load(reader);
var properties = jsonObject.Properties().ToList();
return new Vector2
{
X = (float)properties[0].Value,
Y = (float)properties[1].Value
};
}
public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
{
Vector2 v = (Vector2)value;
writer.WriteStartObject();
writer.WritePropertyName("X");
serializer.Serialize(writer, v.X);
writer.WritePropertyName("Y");
serializer.Serialize(writer, v.Y);
writer.WriteEndObject();
}
}
现在,我注意到写被调用,但读从不被调用。我像这样反序列化:
JsonConvert.DeserializeObject<EntityJson>(json, JsonUtility.Settings);
JsonUility.Settings
包含Vector2Converter
。
而且我这样序列化:
JsonConvert.SerializeObject(entityJson, Formatting.Indented, JsonUtility.Settings);
JSON本身中的字段也看起来不错:
"Center": {
"X": 116.0,
"Y": 65.0
},
有人可以帮我吗?
编辑:
internal class EntityJson
{
public string Name { get; set; }
public Dictionary<string, ComponentJson> Components { get; set; }
public EntityJson()
{
Components = new Dictionary<string, ComponentJson>();
}
public Entity ToEntity()
{
Entity entity = new Entity(Name);
foreach(KeyValuePair<string, ComponentJson> com in Components)
{
ObjectHandle handle = Activator.CreateInstance(com.Value.Namespace, com.Value.Namespace +"."+ com.Key);
Object handleValue = handle.Unwrap();
Component comInstance = (Component)handleValue;
foreach(KeyValuePair<string, object> field in com.Value.Fields)
{
PropertyInfo property = comInstance.GetType().GetProperty(field.Key,
BindingFlags.NonPublic |
BindingFlags.Public |
BindingFlags.Instance);
property.SetValue(comInstance, field.Value); // <-- field.Value
}
entity.AddUnsafe(comInstance);
}
return entity;
}
}
field.value将是一个JObject
而不是一个Vector2
,例外状态是:
无法投射。
确定,我已经通过以下方法解决了它:
object result = field.Value;
if (field.Value.GetType() == typeof(JObject))
{
JToken token = (JToken)field.Value;
result = token.ToObject(property.PropertyType, JsonSerializer.Create(JsonUtility.Settings));
}
else
{
result = Convert.ChangeType(result, property.PropertyType);
}
property.SetValue(comInstance, result);
这是一个稳定的解决方案吗?