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Which design pattern to use when we have classes that does similar high level functionality but the returns different types in methods?

I have an existing C# console application that takes arguments and based on the arguments
creates an instance of markets (UK, US, MX..) using dependency injection.
Each market class does a 'string GetData()', 'string ProcessData()' and 'bool ExportData()'.
The application was initially created for one eCommerce vendor's markets. Now I am told to modify it for a different vendor that does a different process. The high-level flow remains the same.
'GetData' to fetch records from DB,
'ProcessData' for any transformation or the likes
'ExportData'.
The difference is Getdata() pulls records from DB and maps to an object. I am planning to use Petapoco. 'ProcessData' might return a similar class. 'Exportdata' currently does an API call but for the new vendor, I have to write to a file.
I was reading up on patterns I am totally confused. At first, I thought I needed abstract factory pattern and now I think the factory method is what I should be using but I am not sure if I am doing it right. Need some guidance/review here. A sample cs file I created from my understanding of factory pattern. This code is based on the headfirst code samples.
using System;
using System.Collections.Generic;
using StatusExport.Models;
namespace factorymethod
{
class Program
{
static void Main(string[] args)
{
ClientFactory factory = null;
Console.WriteLine("Enter client code:");
string clientCode= Console.ReadLine();
switch (clientCode.ToLower())
{
case "costco":
factory = new CostcoFactory("accountname", "taskname");
break;
//NEw vendor might be added
//case "walmart"
//factory = new WalmartFactory("taskname", "type");
//break
default:
break;
}
bool status = factory.ProcessData();
Console.ReadKey();
}
}
abstract class Client
{
public abstract string AccountName { get; }
public abstract string Task { get; set; }
//More properties might be added. Some may not even be used by some of the new vendors. For example, Costco Might need accountname and task. Tomorrow if walmart comes, they might not need these two or may need task and a new property 'type'
public abstract List<T> GetData<T>();
public abstract List<T> ProcessData<T>();
public abstract bool ExportData();
}
class CostcoClient : Client
{
public override string AccountName { get; }
public override string Task { get; set; }
public CostcoClient(string accountName, string task)
{
AccountName = accountName;
Task = task;
}
public override List<DBRecord> GetData<DBRecord>() //DBRecord class is specific to Costco.
{
List<DBRecord> dbresult = new List<DBRecord>();
//dbresult = db return data mapped to an object DBRecord using petapoco. Another vendor might have a different class to which DB records are mapped. So the return type can be generic
return asn;
}
public override List<T> ProcessData<T>()
{
throw new NotImplementedException(); //Any data transformation or business logic. Return type might be DBRecord or a new class altogether
}
public override bool ExportData()
{
throw new NotImplementedException();//Call API or write data to file and if success send true else false
}
}
abstract class ClientFactory
{
public abstract bool ProcessData();
}
class CostcoFactory : ClientFactory
{
public string AccountName { get; }
public string Task { get; set; }
public CostcoFactory(string accountname, string task)
{
AccountName = accountname;
Task = task;
}
public override bool ProcessData()
{
CostcoClient gc = new CostcoClient(AccountName, Task);
var result = gc.GetData<DBRecord>();
return true;
}
}
}
Do you think this is the right design approach?
I also want to keep the console project independent of vendor project. So maybe 'StatusExport.Program' for the console application. DLL projects StatusExport.Common to hold the interface and abstract classes' and 'StatusExport.Client(ex:StatusExport.Costco)' for each vendor stuff.

You can create BaseClient class that will contains a basic group of properties, and if you need to add something new - just inherit it. You did right, but i think it's better to change public modifier to protected in your properties AccountName and Task, to give access to them only from child classes.
Actually, you can create a BaseClientModels (request/response) for each method if you are not sure that returning type List will be always actual.
Example:
public abstract class BaseClient
{
#region Properties : Protected
protected abstract string AccountName { get; }
protected abstract string Task { get; set; }
#endregion
#region Methods : Public
public abstract BaseGetDataResponseModel GetData(BaseGetDataRequestModel model);
public abstract BaseProcessDataResponseModel ProcessData(BaseProcessDataRequestModel model);
public abstract BaseExportDataResponseModel ExportData(BaseExportDataRequestModel model);
#endregion
}
public class BaseGetDataResponseModel { }
public class BaseGetDataRequestModel { }
public class BaseProcessDataResponseModel { }
public class BaseProcessDataRequestModel { }
public class BaseExportDataResponseModel { }
public class BaseExportDataRequestModel { }
Then let's look on your class CostcoClient and how it can looks like:
public class CostcoClient : BaseClient
{
#region Properties : Protected
protected override string AccountName { get; }
protected override string Task { get; set; }
protected virtual IDataReader<BaseGetDataRequestModel, BaseGetDataResponseModel> DataReader { get; }
protected virtual IDataProcessor<CostcoClientProcessDataRequestModel, CostcoClientProcessDataResponseModel> DataProcessor { get; }
protected virtual IExportDataHandler<CostcoClientExportDataRequestModel, CostcoClientExportDataResponseModel> ExportDataHandler { get; }
#endregion
#region Constructors
public CostcoClient(string accountName, string task)
{
//set DataReader, DataProcessor, ExportDataHandler
AccountName = accountName;
Task = task;
}
#endregion
#region Methods : Public
public override BaseGetDataResponseModel GetData(BaseGetDataRequestModel model)
{
if (model is CostcoClientGetDataRequestModel clientGetDataRequestModel)
{
return DataReader.ReadData(clientGetDataRequestModel);
}
return null; //wrong type has passed
}
public override BaseProcessDataResponseModel ProcessData(BaseProcessDataRequestModel model)
{
if (model is CostcoClientProcessDataRequestModel clientProcessDataRequestModel)
{
return DataProcessor.ProcessData(clientProcessDataRequestModel);
}
return null;
}
public override BaseExportDataResponseModel ExportData(BaseExportDataRequestModel model)
{
if (model is CostcoClientExportDataRequestModel clientExportDataRequestModel)
{
return ExportDataHandler.Handle(clientExportDataRequestModel);
}
return null;
}
#endregion
}
public class CostcoClientGetDataRequestModel : BaseGetDataRequestModel { }
public class CostcoClientGetDataResponseModel : BaseGetDataResponseModel { }
public class CostcoClientProcessDataRequestModel : BaseProcessDataRequestModel { }
public class CostcoClientProcessDataResponseModel : BaseProcessDataResponseModel { }
public class CostcoClientExportDataRequestModel : BaseExportDataRequestModel { }
public class CostcoClientExportDataResponseModel : BaseExportDataResponseModel { }
public interface IDataReader<TIn, TOut>
{
public TOut ReadData(TIn model);
}
public interface IDataProcessor<TIn, TOut>
{
public TOut ProcessData(TIn model);
}
public interface IExportDataHandler<TIn, TOut>
{
public TOut Handle(TIn model);
}
public class CostcoClientDataReader : IDataReader<CostcoClientGetDataRequestModel, CostcoClientGetDataResponseModel>
{
public CostcoClientGetDataResponseModel ReadData(CostcoClientGetDataRequestModel model)
{
throw new NotImplementedException();
}
}
//and so on
You have to implement IDataReader, IDataProcessor, IExportDataHandler, make your logic and call it from GetData, ProcessData, ExportData methods, as an example, and get instances via dependency injection.
Then, we can change your factory to this:
public interface IClientFactory
{
BaseClient GetClientService(ClientServicesEnum value);
}
public class BaseClientFactory : IClientFactory
{
#region Propertied : Protected
protected virtual IEnumerable<BaseClient> Services { get; }
protected string AccountName { get; }
protected string Task { get; set; }
#endregion
#region Constructors
public BaseClientFactory(IEnumerable<BaseClient> services, string accountname, string task)
{
Services = services;
AccountName = accountname;
Task = task;
}
#endregion
public BaseClient GetClientService(ClientServicesEnum value)
=> Services.First(x => x.GetType().Equals(GetClientServiceByCode()[value]));
private Dictionary<ClientServicesEnum, Type> GetClientServiceByCode()
=> new Dictionary<ClientServicesEnum, Type>()
{
{ ClientServicesEnum.CostcoClient, typeof(CostcoClient) }
};
}
public enum ClientServicesEnum
{
CostcoClient = 1,
Another2 = 2,
Another3 = 3
}
Where
protected virtual IEnumerable<BaseClient> Services { get; }
you can get via DI too, and then get correct ServiceHandler by enum.
And your main function to call all this:
switch (clientCode)
{
case 1:
baseClient = ClientFactory.GetClientService(ClientServicesEnum.CostcoClient);
break;
case 2:
baseClient = ClientFactory.GetClientService(ClientServicesEnum.Another2);
break;
default:
break;
}
bool status = baseClient.ProcessData(null); //your model
The main thing is - you can use more than one pattern, for example one from Creational patterns, and one from Structural.
If i need some help in code architecture i use this:
https://refactoring.guru/
I think, using this example you can remove properties AccountName and Task, because of request models in methods.

Is there any solution to handle dataType for TestCaseSource ? [Nunit Framework]

Based on https://gigi.nullneuron.net/gigilabs/data-driven-tests-with-nunit/ website. I have try to create a simple testcase which prepare for read data in the future. But I have no idea how to handle Argument and use it properly
I have try to set as a object, but i think this might not be a correct solution
[TestCaseSource("GetDataString")]
public void TestMethod2(object configs)
{
}
Here is source code
namespace SAP
{
[TestFixture]
public class Scenario1
{
// This one Give System.ArgumentException
[TestCaseSource("GetDataString")]
public void TestMethod(List<Config> configs)
{
Console.WriteLine("Config " + configs);
}
// This one can handle an Exception
[TestCaseSource("GetDataString")]
public void TestMethod2(object configs)
{
}
public static List<Config> GetDataString()
{
var datas = new List<Config>();
datas.Add(new Config("Nick", "Coldson"));
return datas;
}
}
public class Config
{
public string NickName { get; set; }
public string Name { get; set; }
public Config(string nickname, string name)
{
NickName = nickname;
Name = name;
}
}
}
Here is error msg
System.ArgumentException : Object of type 'SAP.Config' cannot be
converted to type 'System.Collections.Generic.List`1[SAP.Config]'.

The testcasesource has slightly different definition pattern. Assuming you use nunit 3 it should be:
[TestCaseSource(typeof(MyTestData), nameof(GetDataString))]
public void TestMethod2(List<Config> configs)
{
...
}
public class MyTestData
{
public static IEnumerable GetDataString()
{
var datas = new List<Config>();
datas.Add(new Config("Nick", "Coldson"));
return new TestCaseData(datas);
}
}
For more info, check the documentation:
https://github.com/nunit/docs/wiki/TestCaseData

Your GetDataString returns a List<Config>.
Meaning, your test method with a [TestCaseSource("GetDataString")] will be executed as many times as many items the list has and your method must match the item type.
//// This one throws System.ArgumentException
//[TestCaseSource("GetDataString")]
//public void TestMethod(List<Config> configs)
//{
// Console.WriteLine("Config " + configs);
//}
// This one is ok
[TestCaseSource("GetDataString")]
public void TestMethod(Config config)
{
Console.WriteLine(config);
}
If you need to get List<Config> instances in your test, then your source must return some collection containing list items.

How can i avoid breaking LSP in this example? C#

I have a base class called Message like this:
public abstract class Message
{
protected int m_id;
protected bool m_localized;
protected string m_metaData;
public int GetID() { return m_id; }
public bool GetLocalized() { return m_localized; }
public string GetMetadata() { return m_metaData; }
}
Then, i have two more classes that inherit from Message for example:
public class ClassicMessage : Message
{
private string m_title;
private string m_content;
public void SetTitle(string title) { m_title = title; }
public void SetContent(string content) { m_content = content; }
public string GetTitle() { return m_title; }
public string GetContent() { return m_content; }
}
public class MessageWithCustomContent : Message
{
private List<CustomContent> m_content;
public MessageWithCustomContent()
{
m_content = new List<CustomContent>();
}
public List<CustomContent> GetContent()
{
return m_content;
}
public CustomContent GetContentEntry(int id)
{
return m_content.find(x => x.ID.Equals(id));
}
}
public class CustomContent
{
private int m_id;
public int ID { get; set { m_id = value; } }
private string m_body;
public string Body { get { return m_body; } set { m_body = value; }
private Image m_image;
public Image Image { get { return m_image; } set { m_image = value; } }
}
In a case like this, how can i unify the app interface if the derived classes has similar methods but these methods have different return types? (even when the methods try to do the same)
I know that with the example i'm breaking the Liskov Substitution Principle and the Open/Closed principle, what's the best approach to get around with that?
Thanks for your help!
Edit:
For more clarity, what i'm trying to achieve is to create a common interface to manage all the possible messages as the base "Message", because i want to avoid using typeof in the consumer class.
for example:
if(message is MessageWithCustomContent)
{
// do something with the contents.
}
else if(message is MessageWithCustomContent)
{
// do another thing with the contents.
}
etc...

You could change Message to be generic, and the T would specify the Content return type. See example below.
Edit
You could use a "IMessage" and a "Message: IMessage" as base.
You would then be able to create a IMessage list like so
var messages = new List<IMessage>
{
new ClassicMessage(),
new MessageWithCustomContent()
};
foreach (var message in messages)
{
message.GetContent();
}
Below is how the implementation of IMessagecould be done.
public interface IMessage
{
int GetID();
bool GetLocalized();
string GetMetadata();
object GetContent();
}
public abstract class Message<T> : IMessage
{
protected int m_id;
protected bool m_localized;
protected string m_metaData;
public int GetID() { return m_id; }
public bool GetLocalized() { return m_localized; }
public string GetMetadata() { return m_metaData; }
object IMessage.GetContent()
{
return GetContent();
}
public abstract T GetContent();
}
public class ClassicMessage : Message<string>
{
private string m_title;
private string m_content;
public void SetTitle(string title) { m_title = title; }
public void SetContent(string content) { m_content = content; }
public string GetTitle() { return m_title; }
public override string GetContent()
{
return m_content;
}
}
public class MessageWithCustomContent : Message<List<CustomContent>>
{
private List<CustomContent> m_content;
public MessageWithCustomContent()
{
m_content = new List<CustomContent>();
}
public CustomContent GetCustomContent(int id)
{
return null;
}
public override List<CustomContent> GetContent()
{
return m_content;
}
}
public class CustomContent
{
private int m_id;
public int ID { get; set; }
private string m_body;
public string Body
{
get { return m_body; }
set { m_body = value; }
}
}

I will explain how you break LSP below but before I do that, you are not really doing any inheriting. Yes you are declaring your classes to be inheriting but you are not really inheriting anything. So before learning LSP, perhaps you need to get a grip on inheritance firstly.
How do I know if I am breaking LSP?
Lest say your Message class was like this, notice the virtual and abstract methods:
public abstract class Message
{
protected int m_id;
protected bool m_localized;
protected string m_metaData;
public virtual int GetID() { return m_id; }
public virtual bool GetLocalized() { return m_localized; }
public abstract string GetMetadata();
}
Create a list like this:
var messages = new List<Message>();
Then add concrete types to that list of all the inheriting types. Then do this:
foreach(var thisMessage in messages)
{
var id = thisMessage.GetID();
var loc = GetLocalized();
var meta = GetMetadata();
}
If you get no exception thrown because one of the inheriting classes decided it does not need one of those methods, then you have not broken LSP. The idea is that if something is inheriting Message, then it should inherit everything. Otherwise, we cannot safely and with confidence substitute the inherited one for the parent one.
The reason this principle is important is because there may be existing code which is using Message, as shown in the foreach above, where it is treating all the types polymorphically and a developer decides to inherit it like this:
public abstract class BadMessage
{
public override int GetID()
{
throw new InvalidOperationException
("This method is not needed for BadMessage and should not be called");
}
public override bool GetLocalized() { ... }
public override string GetMetadata() { ... }
}
You see this will break existing code. And the worst part is, the compiler will not even be able to catch it, until it surfaces like an ugly bug in production.

Well, you're missing the interface methods in de base class. Abstract functions, that get implemented in the derivative classes. If you get a Message, not knowing what kind it is, how would you request its contents?
You could add derivative-specific methods to your base, but you'd have to implement an not_implemented exception in a virtual implementation in the base class to compensate for all derivatives not implementing it, and add exception handling. But then you should ask yourself: " is this class really a derivative? What do I want to achieve."

How should I return a generic response and response code from all functions in a .NET MVC app?

I want to be able to return a generic response from function calls in the business layer of my MVC application. Most of the time I see an object create function look like this
public int Create(ICNUser item)
{
return this._repository.Create(item);
}
public void Update(ICNUser item)
{
this._repository.Create(item);
}
In this case the _repository is a repository that wraps entity framework.
This works great for a lot of cases but I want more information to be returned and I want to have a success/failure variable and a response code for why this action failed validation. I want to optionally be able to return the inserted object or a selected object.
An example would be a create user function that returns an email can't be blank error and or a user already exists error and based on the error I show the user a different message.
The problem I'm running into is I want to have unit tests cover all of the possible response codes from a function without me having to go look at the code and try to figure out what the possible return values can be. What I'm doing feels like an anti-pattern. Is there a better way to accomplish all of this?
This is what I have now.
public IGenericActionResponse<ICNUser> Create(ICNUser item)
{
return this._repository.Create(item);
}
public IGenericActionResponse Update(ICNUser item)
{
return this._repository.Update(item);
}
Interfaces
namespace Web.ActionResponses
{
public enum ActionResponseCode
{
Success,
RecordNotFound,
InvalidCreateHash,
ExpiredCreateHash,
ExpiredModifyHash,
UnableToCreateRecord,
UnableToUpdateRecord,
UnableToSoftDeleteRecord,
UnableToHardDeleteRecord,
UserAlreadyExists,
EmailCannotBeBlank,
PasswordCannotBeBlank,
PasswordResetHashExpired,
AccountNotActivated,
InvalidEmail,
InvalidPassword,
InvalidPageAction
}
public interface IGenericActionResponse
{
bool RequestSuccessful { get; }
ActionResponseCode ResponseCode { get; }
}
public interface IGenericActionResponse<T>
{
bool RequestSuccessful { get; }
bool RecordIsNull{get;}
ActionResponseCode ResponseCode { get; }
}
}
implementations
namespace Web.ActionResponses
{
public class GenericActionResponse<T> : IGenericActionResponse<T>
{
private bool _requestSuccessful;
private ActionResponseCode _actionResponseCode;
public T Item { get; set; }
public GenericActionResponse(bool success, ActionResponseCode actionResponseCode, T item)
{
this._requestSuccessful = success;
this._actionResponseCode = actionResponseCode;
this.Item = item;
}
public GenericActionResponse(bool success, ActionResponseCode actionResponseCode)
{
this._requestSuccessful = success;
this._actionResponseCode = actionResponseCode;
this.Item = default(T);
}
public bool RecordIsNull
{
get
{
return this.Item == null;
}
}
public bool RequestSuccessful
{
get
{
return this._requestSuccessful;
}
}
public ActionResponseCode ResponseCode
{
get
{
return this._actionResponseCode;
}
}
}
public class GenericActionResponse : IGenericActionResponse
{
private bool _requestSuccessful;
private ActionResponseCode _actionResponseCode;
public GenericActionResponse(bool success, ActionResponseCode actionResponseCode)
{
this._requestSuccessful = success;
this._actionResponseCode = actionResponseCode;
}
public bool RequestSuccessful
{
get
{
return this._requestSuccessful;
}
}
public ActionResponseCode ResponseCode
{
get
{
return this._actionResponseCode;
}
}
}}
MVC app
public ActionResult ValidateResetHash(string passwordResetHash)
{
IGenericActionResponse result = (IGenericActionResponse)this._userManager.IsValidPasswordResetHash(passwordResetHash);
if (result.RequestSuccessful)
{
Models.PasswordChangeModel model = new Models.PasswordChangeModel();
model.PasswordResetHash = passwordResetHash;
return View("~/Areas/Public/Views/ResetPassword/PasswordChangeForm.cshtml", model);
}
else
{
switch (result.ResponseCode)
{
case ActionResponseCode.RecordNotFound:
{
FermataFish.Models.GenericActionModel responseModel = new FermataFish.Models.GenericActionModel(true, "/Login", "Login", "You have submitted an invalid password reset link.", false);
return View("~/Views/Shared/GenericAction.cshtml", responseModel);
}
case ActionResponseCode.PasswordResetHashExpired:
{
FermataFish.Models.GenericActionModel responseModel = new FermataFish.Models.GenericActionModel(true, "/ResetPassword", "Reset Password", "You have submitted an expired password reset link. You must reset your password again to change it.", false);
return View("~/Views/Shared/GenericAction.cshtml", responseModel);
}
default:
{
FermataFish.Models.GenericActionModel responseModel = new FermataFish.Models.GenericActionModel(true, "/", "Home", "An unknown error has occured. The system administrator has been notified. Error code:" + Enum.GetName(typeof(ActionResponseCode), result.ResponseCode), false);
return View("~/Views/Shared/GenericAction.cshtml", responseModel);
}
}
}
}

The switch statement in your ValidateResetHash response is a tad code smelly. This would suggest to me that you may benefit from the use of a subclassable enum. The subclassable enum would map action response codes or types to return views with models. Here is a compiling example of how to use this.
First some class fills I used to get a compiling example:
public class GenericActionModel
{
private bool v1;
private string v2;
private string v3;
private string v4;
private bool v5;
protected GenericActionModel() {}
public GenericActionModel(bool v1, string v2, string v3, string v4, bool v5)
{
this.v1 = v1;
this.v2 = v2;
this.v3 = v3;
this.v4 = v4;
this.v5 = v5;
}
}
public class ActionResult
{
private GenericActionModel responseModel;
private string v;
public ActionResult(string v, GenericActionModel responseModel)
{
this.v = v;
this.responseModel = responseModel;
}
}
public class PasswordChangeModel : GenericActionModel
{
public object PasswordResetHash
{
get;
set;
}
}
public interface IUserManager
{
Response IsValidPasswordResetHash(string passwordResetHash);
}
Next some infrastructure(framework) classes (I'm using StringEnum base class from the AtomicStack project for the ResponseEnum base class):
public abstract class Response
{
public abstract string name { get; }
}
public class Response<TResponse> : Response where TResponse : Response<TResponse>
{
private static string _name = typeof(TResponse).Name;
public override string name => _name;
}
// Base ResponseEnum class to be used by more specific enum sets
public abstract class ResponseEnum<TResponseEnum> : StringEnum<TResponseEnum>
where TResponseEnum : ResponseEnum<TResponseEnum>
{
protected ResponseEnum(string responseName) : base(responseName) {}
public abstract ActionResult GenerateView(Response response);
}
Here are some sample responses:
public class HashValidated : Response<HashValidated>
{
public string passwordResetHash;
}
public class InvalidHash : Response<InvalidHash> {}
public class PasswordResetHashExpired : Response<PasswordResetHashExpired> {}
public class Unexpected : Response<Unexpected> {}
A sample subclassable enum mapping the sample responses would look something like this:
public abstract class ValidateHashResponses : ResponseEnum<ValidateHashResponses>
{
public static readonly ValidateHashResponses HashOk = HashValidatedResponse.instance;
public static readonly ValidateHashResponses InvalidHash = InvalidHashResponse.instance;
public static readonly ValidateHashResponses PasswordResetHashExpired = PasswordResetHashExpiredResponse.instance;
public static readonly ValidateHashResponses Default = DefaultResponse.instance;
private ValidateHashResponses(string responseName) : base(responseName) {}
protected abstract class ValidateHashResponse<TValidateHashResponse, TResponse> : ValidateHashResponses
where TValidateHashResponse : ValidateHashResponse<TValidateHashResponse, TResponse>, new()
where TResponse : Response<TResponse>
{
public static TValidateHashResponse instance = new TValidateHashResponse();
private static string name = Response<TResponse>.Name;
protected ValidateHashResponse() : base(name) {}
}
protected class HashValidatedResponse : ValidateHashResponse<HashValidatedResponse, HashValidated>
{
public override ActionResult GenerateView(Response response)
{
PasswordChangeModel model = new PasswordChangeModel();
model.PasswordResetHash = ((HashValidated) response).passwordResetHash;
return new ActionResult("~/Areas/Public/Views/ResetPassword/PasswordChangeForm.cshtml", model);
}
}
protected class InvalidHashResponse : ValidateHashResponse<InvalidHashResponse, InvalidHash>
{
public override ActionResult GenerateView(Response response)
{
GenericActionModel responseModel = new GenericActionModel(true, "/Login", "Login", "You have submitted an invalid password reset link.", false);
return new ActionResult("~/Views/Shared/GenericAction.cshtml", responseModel);
}
}
protected class PasswordResetHashExpiredResponse : ValidateHashResponse<PasswordResetHashExpiredResponse, PasswordResetHashExpired>
{
public override ActionResult GenerateView(Response response)
{
GenericActionModel responseModel = new GenericActionModel(true, "/ResetPassword", "Reset Password", "You have submitted an expired password reset link. You must reset your password again to change it.", false);
return new ActionResult("~/Views/Shared/GenericAction.cshtml", responseModel);
}
}
protected class DefaultResponse : ValidateHashResponses
{
public static DefaultResponse instance = new DefaultResponse();
private DefaultResponse() : base("Default") {}
public override ActionResult GenerateView(Response response)
{
GenericActionModel responseModel = new GenericActionModel(true, "/", "Home", "An unknown error has occured. The system administrator has been notified. Error code:" + response.name, false);
return new ActionResult("~/Views/Shared/GenericAction.cshtml", responseModel);
}
}
}
Implementing the SampleController:
public class SampleController
{
private IUserManager _userManager;
public ActionResult ValidateResetHash(string passwordResetHash)
{
Response result = this._userManager.IsValidPasswordResetHash(passwordResetHash);
var resultType = ValidateHashResponses.TrySelect(result.name,ValidateHashResponses.Default);
return resultType.GenerateView(result);
}
}
Tweak the code above to fit your situation.
If you want to allow others to extend the ValidateHashResponses enum, you can make the constructor protected instead of private. They can then extend ValidateHashResponses and add their own additional enum values.
The point of using the subclassable enum, it to take adavantage of the TrySelect method that resolves responses to a specific enum value. Then we call the GenerateView method on the enum value to generate a view.
Another benefit of the enum is that if you need to have other decisions made based on the enum value, you simply add another abstract method to the enum and all value definitions will be forced to implement the new abstract method, unlike traditional enum/switch statement combinations where new enum values are not required to have cases added and where one may forget to revisit all of the switch statements where the enum was used.
DISCLAIMER:
I'm am the author of the AtomicStack project. Feel free to take the Subclassable enum class code from the project if you feel it would suit your needs.
UPDATE:
If you want to inject the response enum, you should create an IResponseHandler adapter interface with a GenerateViewForResponse type method and provide a concrete implementation that consumes the ValidateHashResponses enum.

How to "send" a method to inside another method?

I have the following:
public class Mail {
public String Obfuscate(String email) {
return email.Replace("#", "at").Replace(".", "dot");
}
}
I am calling the method Obfuscate in a class, as follows:
public class Resolver {
public Data GetData () {
return new Data { Email = new Mail().Obfuscate(myEmail) };
}
public String Translate(string value) { /* Some Code */ }
}
The problem is that Obfuscate does the replacement in English: # > at, . > dot
But in the Resolver class the method Translate does exactly what I need ...
How can I "pass" the Translate method to the Obfuscate method so this one uses it to translate # and . to at and dot in the current language?
So the code line inside Obfuscate:
return email.Replace("#", "at").Replace(".", "dot");
Would be become:
return email.Replace("#", Translate("#")).Replace(".", Translate("."));
Where Translate would be the method that I am "passing" to it.
Than You,
Miguel

Consider a different design:
public interface ITranslator
{
string Translate(string s);
}
public class Obfuscator
{
public Obfuscator(ITranslator translator)
{
this.translator = translator;
}
public string Obfuscate(string email)
{
var at = translator.Translate("at");
var dot = translator.Translate("dot");
return email.Replace("#", at).Replace(".", dot);
}
private ITranslator translator;
}
public class EnglishTranslator : ITranslator
{
public string Translate(string s)
{
return s;
}
}
public class PolishTranslator : ITranslator
{
public PolishTranslator() //or `FileInfo dictionaryFile` parameter perhaps
{
// for simplicity
translations = new Dictionary<string, string>();
translations.Add("at", "malpa");
translations.Add("dot", "kropka");
}
public string Translate(string s)
{
return translations[s];
}
private Dictionary<string, string> translations;
}
However you really should consider using a ResourceManager. Resource related mechanisms are designed to deal with translations.

I think #BartoszKP's answer is the right design decision. For completeness, here's how to do what you asked.
Change Mail to take a Func<string,string>:
public class Mail {
public String Obfuscate(String email, Func<string,string> translate) {
return email.Replace("#", translate("at")).Replace(".", translate("dot"));
}
}
And pass your Translate method to it:
public class Resolver {
public Data GetData () {
return new Data { Email = new Mail().Obfuscate(myEmail, Translate) };
}
public String Translate(string value) { /* Some Code */ }
}