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How can I work out this part of a class diagram?

For school homework I'm supposed to work out a class diagram in C#. Everything went smoothly, but I'm struggling with the constructor for the Track part.
So I think I have to convert a SectionTypes -> Section to put it in the LinkedList, but this doesn't seem logical to me, or am I missing something? Should I convert it in any way or is my overall code for Section wrong?
Here is the class diagram
Here is the part of Section:
namespace Model
{
public enum SectionTypes { Straight, LeftCorner, RightCorner, StartGrid, Finish }
internal class Section
{
public SectionTypes SectionType { get; set; }
}
}
And finally here is where I'm trying to make the constructor, Track:
namespace Model
{
internal class Track
{
public string Name { get; set; }
public LinkedList<Section> Sections { get; set; }
public Track(string name, SectionTypes[] sections)
{
Name = name;
// set Sections here
}
}
}
The error that I get is CS1503, when I try to add anything to Sections in the front, which means the types aren't the same.
Thanks for reading, and thank you for helping in advance!

Here's what I did. By the way, I renamed the SectionTypes enumeration to SectionType (that way, it reads SectionType.Finish, not SectionTypes.Finish).
First I created the enum the same as you:
public enum SectionType
{
Straight,
LeftCorner,
RightCorner,
StartGrid,
Finish,
}
and the Section class pretty much the same way:
public class Section
{
public SectionType SectionType { get; set; }
}
I'm not sure why the class diagram is laid out the way it is, but you need to translate a SectionType to a Section in order to get it to work. That's pretty easy; a Section is a pretty stupid/simple wrapper around a single SectionType. So, things end up looking like:
public class Track
{
public string Name { get; set; }
public LinkedList<Section> Sections { get; set; } = new LinkedList<Section>();
public Track(string name, SectionType[] sections)
{
Name = name;
foreach (var section in sections)
{
Sections.AddLast(new Section { SectionType = section });
}
}
}
Note that I construct the Sections LinkedList. It can either be done the way I show, or it could be done in the constructor. But, the magic is to convert the incoming SectionType[] sections into a collection of Section type. I'm sure that there is a way to do this with LINQ (though I don't have a lot of experience with the LinkedList collection). But, doing it explicitly like this makes it more clear.

Need help deserializing C# / .NET 6 into seperate objects

I am attempting to use JsonSerializer.Deserialize() from System.Text.JSON in .NET 6.
I have no control over the format of the JSON.
I have used it successfully in the past but now the data I need to consume is more complicated (but not VERY complicated). I am assuming that I am simply describing my data incorrectly.
I have tried several things.... but the description below is the only way so far that I could consume the data at all.
I think my biggest problem is that I am trying to use the wiz-bang "Paste Special -> Paste JSON as Classes" without really understanding how to form my classes for serialization/deserialization.
Here is a simple example of the JSON I am trying to consume:
[
{
"version": "1.0b",
"sub_version": "x.y.barf"
},
{
"somestring": "I am a string",
"isCool": false,
"a_cool_array": [
"bob",
"jill",
"pete"
]
}
]
If I use the whiz-bang "Paste Special" tool, I get the following generated for me.
public class Rootobject
{
public Class1[] Property1 { get; set; }
}
public class Class1
{
public string version { get; set; }//<-- I need these to remain in their own object
public string sub_version { get; set; }//<-- I need these to remain in their own object
public string somestring { get; set; }
public bool isCool { get; set; }
public string[] a_cool_array { get; set; }
}
Here is the problem that I have.
The whiz-bang tool put my first object (with one version strings) and second (more complicated) object into the same object.
If I use a call like this:
var deserializedJSON = JsonSerializer.Deserialize<List<Class1>>(myJSONTextHere);
I end up with two objects in the list.
The first one has the versions filled out, the second one only has the other fields filled out.
This all makes sense to me but I don't know how to get around the problem.
I need these objects to model the JSON and I need them to save back in the same format when I re-serailize the modified classes elsewhere. This isn't my exact problem as I have simplified it for the question.

I have found one way around this problem.
It is ugly but seems to work. I hate that my code has to know about the data it is manipulating.
I used the actual JSON DOM to split the two disparate classes into individual JSON objects, then used the class de-serializer to load the individual objects into their given types.
In the following example, I am not checking anything.. I happen to know the order of the objects. I could check the raw JSON to make sure it was what I was looking for. In this case, I don't need to.
So, instead of taking the class structure as pasted by the super spiffy "Paste Classes from JSON" thingamajigger.. I split the classes myself.
Like this:
public class VersionClass
{
public string version { get; set; }
public string sub_version { get; set; }
}
public class DataClass
{
public string somestring { get; set; }
public bool isCool { get; set; }
public string[] a_cool_array { get; set; }
}
Then, I can load the JSON into the objects I need like this:
using var jsonDoc = JsonDocument.Parse(jsonText);
var versionClass = jsonDoc.RootElement[0].Deserialize<VersionClass>();
var dataClass = jsonDoc.RootElement[1].Deserialize<DataClass>();
I hope this helps someone having the same problem.

Your json needs to look like this:
{
"class1": [
//more json
],
"class2": [
//more json
]
}
Then you will have:
public class RootObject
{
// class1 and 2 in here
}
public class Class1
{
}
public class Class2
{
}

iterating through objects of response JSON

I'm doing a query and get as result something like this, which i put into a Hashtable
{"success":"true", "result":[{"type":"email", "address":"aaasd#asd.com"},{"type":"email", "address":"aaasddee#dse.com"}]}
then i do
return hashtable["result"];
so I only have this left
[{"type":"email", "address":"aaasd#asd.com"},{"type":"email", "address":"aaasddee#dse.com"}]
but my problem is that I don't know how to iterate through every object from "result" to fill my own objects. I was searching for a solution but the only answer I found was to use
foreach(DictionaryEntry entry in searchResult) {
//do something<br>
}
When I iterate through the Hashtable like this I can only use the properties entry.Key and entry.Value but I can't say which value for a specific key I need. Any suggestions are welcome.

You can get it using deserialising using JSON.NET as shown below :-
var result = JsonConvert.DeserializeObject<dynamic>(searchResult);
You can create your class like below :-
public class RootObject
{
public string type { get; set; }
public string address { get; set; }
}
For more information :-
http://james.newtonking.com/json/help/index.html?topic=html/SerializingJSON.htm

Create a class that matches the signature of the result collection like:
public class Result
{
public string Type { get; set; }
public string Address { get; set; }
}
Then use Json.NET to parse the result node into a List<Result>. There is plenty of documentation online on how to use the Json.NET library.
Hope that helps,
Rob

ServiceStack C# strongly typed client DTO

Here: Recommended ServiceStack API Structure and here: https://github.com/ServiceStack/ServiceStack/wiki/Physical-project-structure are recommendations for how to structure your projects for C# clients to reuse DTOs.
Apparently this is done by including a dll of the DTO assembly. I have searched the web for one example, just Hello World that uses a separate assembly DTO for a C# client in ServiceStack. Perhaps I should be able to break this out myself but so far it has not proven that easy.
Almost all client descriptions are for generic and non-typed JSON or other non-DTO based clients. No one appears interested in typed C# clients like I am (even the ServiceStack documentation I have found). So I thought this would be a good question even if I figure it out myself in the end.
To be clear, I have built and run the Hello World example server. I have also used a browser to attach to the server and interact with it. I have also created a client empty project that can call
JsonServiceClient client = new JsonServiceClient(myURL);
Then I tried to copy over my DTO definition without the assembly DLL as I don't have one. I get ResponseStatus is undefined.
Clearly there is something missing (it appears to be defined in ServiceStack.Interfaces.dll) and if I could create a dll of the DTO I think it would resolve all references.
Can anyone give insight into how to create the DTO assembly for the simple Hello World?
Edited to add code:
using ServiceStack.ServiceClient.Web;
namespace TestServiceStack
{
class HelloClient
{ public class HelloResponse
{
public string Result { get; set; }
public ResponseStatus ResponseStatus { get; set; } //Where Exceptions get auto-serialized
}
//Request DTO
public class Hello
{
public string Name { get; set; }
}
HelloResponse response = client.Get(new Hello { Name = "World!" });
}
}
Where the ResponceStatus is undefined.

I was able to find the missing symbol ResponseStatus by adding:
using ServiceStack.ServiceInterface.ServiceModel;
Here is the full code that built. Keep in mind that I found out something else in the process. Once this built it then failed because I was using a DTO from a .NET 4.0 environment in a .NET 3.5 environment. But that is an unrelated issue. Also note that this test code does nothing with the response, it is just an example to get the build working.
using ServiceStack.ServiceClient;
using ServiceStack.ServiceInterface;
using ServiceStack.Text;
using ServiceStack.Service;
using ServiceStack.ServiceHost;
using ServiceStack.WebHost;
using ServiceStack;
using ServiceStack.ServiceClient.Web;
using RestTestRoot; // This is the name of my DTO assembly. You will need to insert your own here.
using ServiceStack.ServiceInterface.ServiceModel;
namespace WebApplicationRoot
{
class HelloClient
{
JsonServiceClient hello_client;
//Request DTO
public class Hello
{
public string Name { get; set; }
}
//Response DTO
public class HelloResponse
{
public string Result { get; set; }
public ResponseStatus ResponseStatus { get; set; } //Where Exceptions get auto-serialized
}
//Can be called via any endpoint or format, see: http://mono.servicestack.net/ServiceStack.Hello/
public class HelloService : Service
{
public object Any(Hello request)
{
return new HelloResponse { Result = "Hello, " + request.Name };
}
}
//REST Resource DTO
[Route("/todos")]
[Route("/todos/{Ids}")]
public class Todos : IReturn<List<Todo>>
{
public long[] Ids { get; set; }
public Todos(params long[] ids)
{
this.Ids = ids;
}
}
[Route("/todos", "POST")]
[Route("/todos/{Id}", "PUT")]
public class Todo : IReturn<Todo>
{
public long Id { get; set; }
public string Content { get; set; }
public int Order { get; set; }
public bool Done { get; set; }
}
public HelloClient(){
// ServiceStack gateway = new ServiceStack.ClientGateway(
// location.protocol + "//" + location.host + '/ServiceStack.Examples.Host.Web/ServiceStack/');
hello_client = new JsonServiceClient("http://tradetree2.dnsapi.info:8080/");
hello_client.Get<HelloResponse>("/hello/MyTestWorld!");
}
}
}

JSON Deserialization in .NET

I've had a look at a few threads but what I'm aiming for I can't seem to find.
I have the following JSON strings returned:
On success:
{"success":{"username":"key"}}
On Error:
{"error":{"type":101,"address":"/","description":"link button not pressed"}}
I need to be able to de-serialize these into a class and determine whether I've got an error or a success message to carry on doing it. Any ideas on how to achieve this?
thanks,
Adam

No need to declare a lot of tiny classes. dynamic keyword can help here.
dynamic jObj = JObject.Parse(json);
if (jObj.error!= null)
{
string error = jObj.error.description.ToString();
}
else
{
string key = jObj.success.username.ToString();
}

One option is to use http://nuget.org/packages/newtonsoft.json - you can either create your own custom class to deserialize into or use dynamic as the target type.
var result = JsonConvert.DeserializeObject<Result>(jsonString);
class Result
{
public SuccessResult success { get; set; }
public ErrorResult error { get; set; }
}
class SuccessResult
{
public string username { get; set; }
}
class ErrorResult
{
public int type { get; set; }
public string address { get; set; }
public string description { get; set; }
}
If you need just to check for success, it is possible to just check result.StartsWith("{\"success\":") to avoid unnecessary parsing. But this should only be done if you have guarantee that the JSON string will always be exactly like this (no extra whitespaces etc.) - so it is usually only appropriate if you own the JSON generation yourself.

This answer covers most options, including rolling your own parser and using JSON.Net:
Parse JSON in C#
You could also just write a regex if the format is going to be that simple...