本文介绍了如何递归调用WriteJson?的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我使用Json.Net.当我序列化Department2对象并调用WriteJson()时，我希望它像在ReadJson()中所做的那样与每个Telephone2对象一起递归调用.
I use Json.Net.When I serialize a Department2 object and WriteJson() is invoked I want it to be recursively invoked with each of the Telephone2 objects like I do in ReadJson().
我该怎么做?
using System;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
public interface ISimpleDatabag
{
string Databag { get; set; }
}
[JsonConverter(typeof(JsonDataBagCreationConverter<Department2>))]
public class Department2
{
public Telephone2[] Phones { get; set; }
}
[JsonConverter(typeof(JsonDataBagCreationConverter<Telephone2>))]
public class Telephone2
{
public string Name { get; set; }
public string AreaCode { get; set; }
public string Number { get; set; }
}
public class JsonDataBagCreationConverter<T> : JsonConverter where T : new()
{
// Json.Net version 4.5.7.15008
public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
{
// When I serialize Department and this function is invoked
// I want it to recursively invoke WriteJson with each of the Telephone objects
// Like I do in ReadJson
// How do I do that?
T t = (T)value;
serializer.Serialize(writer, t.GetType());
}
public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
{
var jsonObject = JObject.Load(reader);
var target = Create(objectType, jsonObject);
serializer.Populate(jsonObject.CreateReader(), target); // Will call this function recursively for any objects that have JsonDataBagCreationConverter as attribute
return target;
}
protected T Create(Type objectType, JObject jsonObject)
{
return new T();
}
public override bool CanConvert(Type objectType)
{
return typeof(T).IsAssignableFrom(objectType);
}
}
private void Form1_Load(object sender, EventArgs e)
{
string jsonInput = "{\"Name\": \"Seek4\" , \"CustomDepartmentData\": \"This is custom department data\", \"Phones\":[ {\"Name\": \"A\", \"AreaCode\":444, \"Number\":11111111} ,{\"Name\": \"B\", \"AreaCode\":555, \"Number\":987987987}, {\"Name\": \"C\", \"AreaCode\":222, \"Number\":123123123, \"CustomPhoneData\": \"This is custom phone data\"} ] }";
Department2 objDepartment2 = JsonConvert.DeserializeObject<Department2>(jsonInput); // Yes, it works well
Array.Reverse(objDepartment2.Phones);
string jsonNoDatabag = JsonConvert.SerializeObject(objDepartment2);
}
推荐答案
我最终使用这个庞大的函数(未重构)来控制整个过程.我基本上研究了对象的每个属性以进行序列化，然后逐个属性地对其进行序列化.然后我可以对每个属性进行自定义操作
I ended up controlling the entire process myself, using this huge (not refactored) function.I basically investigate each of the properties of the object to serialize and then serialize it property by property.Then I can do custom things on each property
/// <summary>
/// Serializes an object by merging its current values into its databag and returns the databag
/// </summary>
/// <param name="objectToSerialize"></param>
/// <returns>the current values merged into the original databag</returns>
/// <remarks>Jan Nielsen, 01-10-2012</remarks>
internal static string SerializeObjectToDatabag(object objectToSerialize)
{
// You have to do it property by property instead of just serializing the entire object and merge it into the original
// because the object might contain lists of objects with custom data and these list might have been sorted differently from when they were loaded
// So you cannot merge them properly unless you do it on a per listitem basis.
// Which is what I do here.
try
{
if (objectToSerialize == null) // If you ie serialize an empty object in an array
{
return null;
}
string updatedDatabag = "";
bool isIDataBag = objectToSerialize is IDataBag;
if (isIDataBag)
{
updatedDatabag = ((IDataBag)objectToSerialize).Data == null ? "" : ((IDataBag)objectToSerialize).Data.ToString();
// updatedDatabag = ((IDataBag)objectToSerialize).Data.ToString(); // Save original data in a local variable. This is the one we will merge new values into
}
string result = "";
// Now iterate through the objects properties
// Possible properties:
// Simple types: string, int, bool etc: their current value should be overwritten in the databag
// types that implement IDatabag: they should be sent to this function recursively so their possible customdata is not overwritten
// but instead their simple values are merged into their own databag. Then the result of this single property merge is overwritten in the outer objects databag
// Types that are not simple and don't implement IDatabag but have properties that implement IDatabag
// types that are not simple and don't implement IDatabag and don't have any properties in any depth that implement IDatabag: They are overwritten in the databag
// Types that are arrays:
// If the types in the array are simple types (string, bool etc) the entire array property is overwritten in the databag
// If the types in the array implement IDatabag each object is sent recursively to this function and their databag is updated via merge
// Then the entire array is overwritten in the outer objects databag
// Types that are generic list are treated like arrays
var properties = objectToSerialize.GetType().GetProperties();
// In order to be able to deserialize abstract classes and interfaces, we need to serialize the classname with the class
// the deserializer recognizes the word $type followed by a type, when its is invoked with a serializerSettings of
// serializerSettings.TypeNameHandling = TypeNameHandling.Objects;
string name = objectToSerialize.GetType().AssemblyQualifiedName;
string shortName = RemoveAssemblyDetails(name);
bool addedType = false;
foreach (var propertyInfo in properties)
{
if (propertyInfo.Name.ToLower() != "data") // Just skip Databag. Databag is not a "real" property but the contents of all the properties when the object was loaded + possible custom data
{
if (!addedType)
{
string jsonSingleProperty = "{ " + ToCustomJson("$type") + " : " + ToCustomJson(shortName) + " }";
// Merge the current value (jsonSingleProperty) into the databag (that might already have been updated with the values of other properties)
// and update the current result with the new values. Ie "Name" : "Seek4" is updated to "Name" : "Seek4Cars" in the databag
// and the function will now use the updated databag to merge the other properties into
updatedDatabag = MergeDefault(jsonSingleProperty, updatedDatabag, true);
addedType = true;
}
// propertyInfo.Name.ToLower().Contains("struct")
var value = propertyInfo.GetValue(objectToSerialize, null); // This gets the value of the specified property in the current object
isIDataBag = value is IDataBag; // Update for the current object. Note that ie an array of IDatabag will return false here, because array is not IsimpleDatabag
// Basically we should just check if the property implements IDatabag
// But the simpletype check is faster because I don't have to check for the interfaces on ie a string, int etc.
// This branch takes care of 3 cases:
// 1) it is a simple type, ie int
// 2) value is null
// 3) it is an array with a value of null
// If an array with values enters this branch of code the values of the array will be appended, overwritten
// Therefore arrays are treated below in a special case. Unless they are null
// GeneralFunctions.IsExtendedSimpleType_AllTypes(propertyInfo.PropertyType) returns true on ie string[], but only arrays with a value of null should be handled here
// This first check originally just checked for simple types
// Then it became extended simple types ie non-simple types that only contains simple types ie List<int,int>
// But not arrays that must be handled separately
// Then it also handled null values
// And then a special case was made for arrays that are null
if ((GeneralFunctions.IsExtendedSimpleType_AllTypes(propertyInfo.PropertyType) || value == null) && (!propertyInfo.PropertyType.IsArray || (propertyInfo.PropertyType.IsArray && value == null)))
{
// You have to merge even though it is default value.
// If you have ie a bool that has an initial value of true and you deliberately sets it to false
// You want the defaultvalue of false to be merged into the json.
string jsonSingleProperty = "{" + ToCustomJson(propertyInfo.Name) + " : " + ToCustomJson(value) + "}"; // ie {"Name" : "Seek4Cars"}
// Merge the current value (jsonSingleProperty) into the databag (that might already have been updated with the values of other properties)
// and update the current result with the new values. Ie "Name" : "Seek4" is updated to "Name" : "Seek4Cars" in the databag
// and the function will now use the updated databag to merge the other properties into
updatedDatabag = MergeDefault(jsonSingleProperty, updatedDatabag, true);
continue;
}
if (isIDataBag) // ie PhoneSingle. A single property of type IDataBag
{
// Invoke recursively
// First check if this is an object with all null values
bool allPropertiesAreNull = true; // Maybe this should in the future be expanded with a check on if the property has its default value ie an int property with a value of 0
foreach (var propertyInfoLocal in value.GetType().GetProperties())
{
var valueLocal = propertyInfoLocal.GetValue(value, null);
if (valueLocal != null)
{
allPropertiesAreNull = false;
break;
}
}
var testjson = "";
if (allPropertiesAreNull)
{
result = "{" + ToCustomJson(propertyInfo.Name) + " : " + " { } }";
}
else
{
testjson = ToCustomJson(value);
result = "{" + ToCustomJson(propertyInfo.Name) + " : " + SerializeObjectToDatabag(value) + "}";
}
updatedDatabag = MergeDefault(result, updatedDatabag, true);
continue;
}
bool containsIDataBag = CheckForDatabagInterfaces.ImplementsInterface(propertyInfo.PropertyType, "idatabag"); // Check if anything inside the property implements IDatabag ie an array of IDatabag
if (containsIDataBag)
{
// Check if it is somekind of generic list (List<T>, Dictionary<T,T) etc) and if it is a type of ignoreTypes ie List<entity>)
if (value.GetType().IsGenericType && value.GetType().GetGenericArguments().Length > 0)
{
string listValuesAsJson = "";
if (value is IEnumerable)
{
listValuesAsJson += "{ " + ToCustomJson(propertyInfo.Name) + " : [";
bool containsItems = false;
foreach (var element in (IEnumerable)value)
{
containsItems = true;
var current = SerializeObjectToDatabag(element);
if (current != null) // If you serialize an empty array element it is null
{
listValuesAsJson += current + ", "; // Add , between each element
}
}
if (containsItems)
{
listValuesAsJson = listValuesAsJson.Substring(0, listValuesAsJson.Length - 2) + "] }"; // remove last , and add ending ] for the array and add a } because this property is flowing in the free
}
else // No items in value
{
listValuesAsJson += "] }"; // add ending ] for the array and add a } because this property is flowing in the free
}
}
else // A single, generic KeyValuePair property
{
listValuesAsJson += "{ " + ToCustomJson(propertyInfo.Name) + " : ";
listValuesAsJson += SerializeObjectToDatabag(value);
listValuesAsJson += " }";
}
updatedDatabag = MergeDefault(listValuesAsJson, updatedDatabag, false);
}
else if (value.GetType().IsArray)
{
string arrayValuesAsJson = "{ " + ToCustomJson(propertyInfo.Name) + " : [";
bool containsItems = false;
foreach (var element in (Array)value)
{
// Treat them the same way you treat any other object
var current = SerializeObjectToDatabag(element);
if (current != null) // If you serialize an empty array element it is null
{
containsItems = true;
arrayValuesAsJson += current + ", ";
}
}
if (containsItems)
{
arrayValuesAsJson = arrayValuesAsJson.Substring(0, arrayValuesAsJson.Length - 2) + "] }"; // remove last , and add ending ] for the array and add a } because this property is flowing in the free
}
else // No items in value
{
arrayValuesAsJson += "] }"; // add ending ] for the array and add a } because this property is flowing in the free
}
updatedDatabag = MergeDefault(arrayValuesAsJson, updatedDatabag, false);
}
else if ( value.GetType().BaseType != null && value.GetType().BaseType.FullName.ToLower().Contains("system.collections.objectmodel"))
{
// This branch was made specifically to take care of the Media collection of a Seek4.Entities.V2.Media.MediaCollection
var genericList = (IList)value;
int counter = genericList.Count;
string listAsJson = "{ " + ToCustomJson(propertyInfo.Name) + " : [";
if (counter == 0)
{
listAsJson += "] }"; // Ie { "Media": [] }
}
else
{
foreach (var obj in genericList)
{
var current = SerializeObjectToDatabag(obj);
listAsJson += current + ", ";
}
listAsJson = listAsJson.Substring(0, listAsJson.Length -2) + " ] }" ;
}
updatedDatabag = MergeDefault(listAsJson, updatedDatabag, true); // hvordan gør json.net dette med standard?
}
else // a single Non-IDatabag property that contains Idatabag properties
{
string tempResult = "{ " + ToCustomJson(propertyInfo.Name) + " : ";
tempResult += SerializeObjectToDatabag(value) + " }";
updatedDatabag = MergeDefault(tempResult, updatedDatabag, true);
}
}
else
{
if (value.GetType().IsArray) // This is an array of simple types so just overwrite
{
string arrayAsJson = "{ " + ToCustomJson(propertyInfo.Name) + " : ";
arrayAsJson += ToCustomJson(value) + "}";
updatedDatabag = MergeDefault(arrayAsJson, updatedDatabag, false);
}
else // ie an object that is not simpledatabag and doesn't contain simple databag
{
string jsonSingleProperty = "{" + ToCustomJson(propertyInfo.Name) + " : " + ToCustomJson(value) + "}";
updatedDatabag = MergeDefault(jsonSingleProperty, updatedDatabag, true);
}
}
}
}
return updatedDatabag;
}
catch (Exception ex)
{
string message = ex.Message;
string stack = ex.StackTrace;
throw;
}
}
internal static string ToCustomJson(object objectToConvertToJson)
{
try
{
// Distinguished from Mongodb.Bson.ToJson() extensionmethod by Custom name
JsonSerializerSettings serializerSettings = new JsonSerializerSettings();
serializerSettings.TypeNameHandling = TypeNameHandling.Objects; // Adds a $type on all objects which we need when it is abstract classes and interfaces
IgnoreDataMemberContractResolver contractResolver = new IgnoreDataMemberContractResolver(null, true, true);
serializerSettings.ContractResolver = contractResolver;
serializerSettings.DefaultValueHandling = DefaultValueHandling.Ignore;
IsoDateTimeConverter converter = new IsoDateTimeConverter();
serializerSettings.Converters.Add(converter);
string result = JsonConvert.SerializeObject(objectToConvertToJson, Formatting.None, serializerSettings);
return result;
}
catch (Exception ex)
{
throw new Exception("Error in ToCustomJson: " + ex.Message, ex);
}
}
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