I am working on a project that communicates a lot of data with a server. This data is in a json format. We end up creating a lot of dummy objects to parse the json data. This leads to having a lot of classes that just contain class members. Is there a better way of doing things?
thanks
Assuming that you are using NewtonSoft's JSON parser or something similar, you have a couple of choices here. The usual use case here is to deserialize to a named type, thus:
var parsedMessage = JsonConvert.DeserializeObject<Message>(content.AsString());
If you have many types for each differnet JSON message type you wish to receive and wish to avoid to, you can do the following:
var parsedMessage = JsonConvert.DeserializeObject<dynamic>(content.AsString());
This will give you a dynamic object that you can inspect and should also work given other Json libraries. Alternatively, NetwtonSoft also provides the following method:
public static T DeserializeAnonymousType<T>(string value, T anonymousTypeObject);
This will allow you to deserialize to an anonymously typed object rather than a dynamic object.
Related
I have some JSON here. The problem is it doesn't match the classes data types anymore. My question is; is it possible to deserialize JSON Dynamically? i.e. if I have entirely different JSON's can I deserialize them into two entirely different classes without first knowing what class I want to deserialize each into.
You can deserialize dynamic object with using newtonsoft
like bellowing code piece.
dynamic dynamicObj = JsonConvert.DeserializeObject(jsonStr);
string name = dynamicObj.data.code;
But in my personal preference is using strong type. I think its more convenience.
you can use quictype for generating c# classes from JSON object
quicktype generates strongly-typed models and serializers from JSON,
JSON Schema, and GraphQL queries, making it a breeze to work with JSON
type-safely in any programming language.
Hope the answer helps to you.
I have some JSON data :-
{
"mail":"mitch#domain.com",
"givenName":"User",
"sn":"Name",
"uid":"mitch",
"gecos":"User Name"
}
What I'm trying to do is de-serialize this into a List<KeyValuePair<string,string>>
I would normally do a dictionary, however some key's may be duplicated - this is the representation that is automatically generated by .NET when I pass a List<KeyValuePair<string,string>> object into the System.Web.Script.Serialization.JavaScriptSerializer class.
When I just plug the serialized object into the System.Web.Script.Serialization.JavaScriptDeserializer I get a empty response back.
From what I can see it should not be possible using the JavaScriptSerializer. The only way for customizing its behavior is by means of a JavaScriptConverter class, that will allow you to customize the serialization/deserialization process. Unfortunately both methods will pass an IDictionary for the properties, therefore the duplicated names are already merged. You might want to look into either a different format for your JSON or a different serialization library such as JSON.net which is way more customizable.
I have a small WinRT client app to my online service (Azure Web Service). The server sends a JSON encoded object with (with potential additional metadata) to the client and the client's responsibility would be to deserialize this data properly into classes and forward it to appropriate handlers.
Currently, the objects received can be deserialized with a simple
TodoItem todo = JsonConvert.DeserializeObject<TodoItem>(message.Content);
However, there can be multiple types of items received. So what I am currently thinking is this:
I include the type info in the header serverside, such as "Content-Object: TodoItem"
I define attributes to TodoItem on the client side (see below)
Upon receiving a message from the server, I find the class using the attribute I defined.
I call the deserialization method with the resolved type
(Example of the attribute mentioned in 2.)
[BackendObjectType="TodoItem"]
public class TodoItem
My problem with this approach however is the Type to Generics in the deserialization as I can't call:
Type t = ResolveType(message);
JsonConvert.DeserializeObject<t>(message.Content);
I tried finding some solutions to this and getting method info for the DeserializeObject and calling it using reflection seemed to be the way to go. However, GetMethod() does not exist in WinRT and I was not able to find an alternative I could use to retrieve the generic version of the DeserializeObject (as fetching by the name gives me the non-generic overload). I don't mind using reflection and GetMethod as I can cache (?) the methods and call them every time a message is received without having to resolve it every time.
So how do I achieve the latter part and/or is there another way to approach this?
Alright, I feel like this was not really a problem at all to begin with as I discovered the DeserializeObject(string, Type, JsonSerializerSettings) overload for the method. It works splendidly. However, I would still like to hear some feedback on the approach. Do you think using attributes as a way to resolve the type names is reasonable or are there better ways? I don't want to use the class names directly though, because I don't want to risk any sort of man-in-the-middle things be able to initialize whatever.
Just a few minutes ago we have posted the alternative way to do what you want. Please look here, if you will have any questions feel free to ask:
Prblem in Deserialization of JSON
Try this
http://json2csharp.com/
Put your Json string here it will generate a class
then
public static T DeserializeFromJson<T>(string json)
{
T deserializedProduct = JsonConvert.DeserializeObject<T>(json);
return deserializedProduct;
}
var container = DeserializeFromJson<ClassName>(JsonString);
I'm looking for a JSON parser and encoder for .NET that can parse JSON into its own data structure which I can then navigate, as opposed to directly deserializing it into a class. In Java, I use Jettison's JSONObject and JSONArray which is dead easy to use.
There are a number of reasons why I don't want to (de)serialize:
Serializers tend to add metadata to the JSON and require that metadata for deserialization (e.g. fastJSON and JSON.NET add type info).
I don't want the hassle of having to create a bunch of classes to handle all the different types of data. Also, I want to be able to ignore fields I'm not interested in rather than have to add properties to them.
Is there anything available or do I have to port a subset of Jettison?
The disadvantages of serialization that you point out aren't really there, at least in the case of JSON.NET:
JSON.NET doesn't add any metadata by default. You can tell it to add the metadata if you need it (for example, when one property can hold values of different types), but it's optional.
You replace the hassle of creating classes with the hassle of working with strings and casts and I think that's much worse. Also, you can ignore fields you're not interested in, just don't add them to your types.
But, if you really want to do that, you can. The equivalent types are JObject and JArray, so, if you want to deserialize some object, use:
JObject obj = JsonConvert.DeserializeObject<JObject>(json);
As another option, you don't have to specify the type you want at all, ant it will return either JObject or JArray:
object objectOrArray = JsonConvert.DeserializeObject(json);
I need to serialize the strings from a resource file (.resx) into a JSON object. The resource file's keys are in flux and thus I cannot just create a C# object that accepts the appropriate values. It needs to be a dynamic solution. I am able to loop through the key-value pairs for the file, but I need an easy way to serialize them to JSON.
I know I could do:
Object thing = new {stringOne = StringResource.stringOne; ...}
But, I'd rather have something like:
Object generic = {}
foreach (DictionaryEntry entry in StringResource) {
generic.(entry.Key) = entry.Value
}
Or should I just create a custom JSON serializer that constructs the object piecemeal (i.e. foreach loop that appends part of the JSON string with each cycle)?
EDIT
I ended up writing a quick JSON serializer that constructs the string one field at a time. I didn't want to include a whole JSON library as this is the only use of JSON objects (for now at least). Ultimately, what I wanted is probably impractical and doesn't exist as it's function is better served by other data structures. Thanks for all the answers though!
If you're using C# 4.0, you should look at the magical System.Dynamic.ExpandoObject. It's an object that allows you to dynamically add and remove properties at runtime, using the new DLR in .NET 4.0. Here is a good example use for the ExpandoObject.
Once you have your fully populated ExpandoObject, you can probably easily serialize that with any of the JSON libraries mentioned by the other excellent answers.
This sounds like an accident waiting to happen (i.e. creating output prior to cementing the structure), but it happens.
The custom JSON serializer is a compelling option, as it allows you to easily move from your dictionary into a JSON format. I would look at open source libraries (JSON.NET, etc) to see if you can reduce the development time.
I also think setting up in a slightly more structured format, like XML, is a decent choice. It is quite easy to serialize from XML to JSON using existing libraries, so you avoid heavy customization/
The bigger question is what purposes will the data ultimately serve. If you solve this problem using either of these methods, are you creating bigger problems in the future.
Probably I would use JSON.NET and the ability to create JSON from XML.
Then, you could create an XML in-memory and let JSON.NET convert it to JSON for you. Maybe if you dig deeper into the API, there are other options, too.
Newtonsoft is a library that has all kinds of nifty JSON tools...among them, on-the-fly one-line serializer and deserializers...check it out, it's my favorite JSON library out there
http://james.newtonking.com/pages/json-net.aspx
If I remember correctly, it has a class that will convert JSON to a .NET object without having to create the .NET object first. Think it is in the Json.Convert class
The way I do it is:
var serialiser = new System.Web.Script.Serialization.JavaScriptSerializer();
string json = serialiser.Serialize(data);
context.Response.Write(json);