I am new to this forum. Now-days I am studying design patterns. I learnt about factory pattern and implemented simple example as shown below.
public interface IPlc
{
string Name { get; set; }
void Testping();
}
Public AbbPlc : IPlc
{
string Name { get; set; }
string slotnumber { get; set; }// Property relevant with this class
public void Testping()
{
console.writeline("ping executed successfully");
}
}
Public SiemensPlc : IPlc
{
string Name { get; set; }
string Racknumber { get; set; }// Property relevant with this class
public void Testping()
{
console.writeline("ping executed successfully");
}
}
//In Main Program
var objAbb = new IPlc() //Created object from interface
objAbb.Name = "46IC-PLC"; //Works OK
objAbb.slotnumber "3"; //Not works
var objSiemens = new IPlc() //Created object from interface
objSiemens.Name = "45IC-PLC"; //Works OK
objSiemens.Racknumber "5"; //Not works
Could you please tell me why these two methods doesn't work?
What I have to do to access properties from Interface object?
Do I need to use one more pattern with factory like decorator?
Related
Still pretty new to maui and mvvm, I'm trying to figure out of to access elements in a observable property class in a method. For example I have a login class like below:
public class LoginModel
{
public string Failmessage { get; set; } = string.Empty;
public string Username { get; set; } = string.Empty;
public string Password { get; set; } = string.Empty;
public bool Validusername { get; set; } = true;
public bool Vaildpassword { get; set; } = true;
}
In my modelview I call the observable property LoginModel loginModel
[ObservableProperty]
LoginModel LoginModel
public LoginPageViewModel()
{
LoginModel login= new();
}
I want to check the property value in a method like below but it keeps giving me errors. like Fields with [ObservableProperty] should not be directly referenced, and the generated properties should be used instead.
if ((string.IsNullOrEmpty(LoginModel.Username)) || (string.IsNullOrWhiteSpace(LoginModel.Username)))
{
IsBusy = false;
LoginModel.Validusername = false;
return;
}
Am I doing something wrong here?
I want to be able to access the element of the class in a method.
From your code, I found that you should have used nuget CommunityToolkit.Mvvm.
And the problem is that you didn't use CommunityToolkit.Mvvm correctly.
You can try to add prefix partial before class LoginPageViewModel and declare loginmodel starting with small letter,thenLoginmodel property will be generated for you by MVVM Toolkit.
You can refer to the following code:
public partial class LoginPageViewModel:ObservableObject
{
[ObservableProperty]
LoginModel loginmodel;
public LoginPageViewModel() {
//LoginModel login = new();
Loginmodel = new LoginModel();
}
public void Test() {
if ((string.IsNullOrEmpty(Loginmodel.Username)) || (string.IsNullOrWhiteSpace(Loginmodel.Username)))
{
//IsBusy = false;
Loginmodel.Validusername = false;
return;
}
}
}
Update
now the if statement is working but when I set
Loginmodel.Validusername = false; the view is not updating with this
new value.
If you want the UI update automatically once changing the value of model Loginmodel, you also need to implement interface INotifyPropertyChanged for class LoginModel.
Please refer to the following code:
public class LoginModel: INotifyPropertyChanged
{
public string Failmessage { get; set; } = string.Empty;
public string Username { get; set; } = string.Empty;
public string Password { get; set; } = string.Empty;
// public bool Validusername { get; set; } = true;
// modify code as follows
private bool _validusername;
public bool Validusername
{
get => _validusername;
set
{
SetProperty(ref _validusername, value);
}
}
public bool Vaildpassword { get; set; } = true;
bool SetProperty<T>(ref T storage, T value, [CallerMemberName] string propertyName = null)
{
if (Object.Equals(storage, value))
return false;
storage = value;
OnPropertyChanged(propertyName);
return true;
}
protected void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
public event PropertyChangedEventHandler PropertyChanged;
}
ViewModels are ObservableObjects, not ObservableProperties.
They contain ObservableProperties.
Do not construct manually your ViewModels. Use dependency injection and register them as services.
For this what you call "check property value", that are actually ObservableProperties in ObservableObject, there is ObservableValidator class.
https://learn.microsoft.com/en-us/dotnet/communitytoolkit/mvvm/observablevalidator
Fix this, and ask if you have any questions.
I have a Kalem Entity with a collection of DigerKalemMaliyetleri property, which is a collection of MaliyetBirimi objects. DigerKalemMaliyetleri is of JSON type and stored at the same table as a JSON column.
public class Kalem
{
public int Id { get; set; }
[Column(TypeName = "json")]
public ICollection<MaliyetBirimi> DigerKalemMaliyetleri { get; set; }
}
public class MaliyetBirimi
{
public int? DovizCinsi { get; set; }
public decimal? Maliyet { get; set; }
}
When I try to update entity with only DigerKalemMaliyetleri property changed:
DataContext.Entry<Kalem>(first).CurrentValues.SetValues(second);
SQL Update command isn't executed and database record is not updated.
How could I update the entity without explicitly setting DigerKalemMaliyetleri property?
Regards
I had the same problem, you cann't actually use SetValues to update navigation property, you nead instead use DataContext.Update(YourNewObj) and then DataContext.SaveChanges();, or if you want to use SetValues approach, you need:
-Get the exist entry
Kalem existObj = DataContext.Kalems.Find(YourNewObj.Id);
-Loop in navigations of updating entry and the existing one to set the values of updating entry:
foreach(var navObj in DataContext.Entry(YourNewObj).Navigations)
{
foreach(var navExist in DatatContext.Entry(existObj).Navigations)
{
if(navObj.Metadata.Name == navExist.MetaData.Name)
navExist.CurrentValue = navObj.CurrentValue;
}
}
-Update also changes of direct properties:
DataContext.Entry(existObj).CurrentValues.SetValues(YourNewObj);
-Save your Updating:
DataContext.SaveChanges();
You can also check if you need to load your Navigations before going in foreach loop, otherwise you will get an error.
Please if you see beter scenario, correct me.
It's hard to know exactly what you're doing without a complete code sample. Note also that you're trying to set all properties of first from second, including e.g. the Id, which is probably not what you want.
Here's a complete code sample which works for me:
await using (var ctx = new BlogContext())
{
await ctx.Database.EnsureDeletedAsync();
await ctx.Database.EnsureCreatedAsync();
ctx.Kalem.Add(new()
{
DigerKalemMaliyetleri = new List<MaliyetBirimi>()
{
new() { DovizCinsi = 1, Maliyet = 2 }
}
});
await ctx.SaveChangesAsync();
}
await using (var ctx = new BlogContext())
{
var first = ctx.Kalem.Find(1);
var second = new Kalem
{
DigerKalemMaliyetleri = new List<MaliyetBirimi>()
{
new() { DovizCinsi = 3, Maliyet = 4 }
}
};
ctx.Entry(first).Property(k => k.DigerKalemMaliyetleri).CurrentValue = second.DigerKalemMaliyetleri;
await ctx.SaveChangesAsync();
}
public class BlogContext : DbContext
{
public DbSet<Kalem> Kalem { get; set; }
static ILoggerFactory ContextLoggerFactory
=> LoggerFactory.Create(b => b.AddConsole().AddFilter("", LogLevel.Information));
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
=> optionsBuilder
.UseNpgsql(#"Host=localhost;Username=test;Password=test")
.EnableSensitiveDataLogging()
.UseLoggerFactory(ContextLoggerFactory);
}
public class Kalem
{
public int Id { get; set; }
[Column(TypeName = "json")]
public ICollection<MaliyetBirimi> DigerKalemMaliyetleri { get; set; }
}
public class MaliyetBirimi
{
public int? DovizCinsi { get; set; }
public decimal? Maliyet { get; set; }
}
We have an API with about a dozen integration tests. All the tests passed until I added some DTOs and used AutoMapper. Now, all the tests that test methods that use AutoMapper and the DTOs are failing. I have provided all the code needed to understand one of the failing tests. Also, I read a lot about AutoMapper and the following StackOverflow posts:
Integration Testing with AutoMapper fails to initialise configuration
A kind of integration testing in ASP.NET Core, with EF and AutoMapper
Startup.cs
This is our Startup.ConfigureServices(). I have tried every code block commented out and/or marked "ATTEMPTED".
public void ConfigureServices(IServiceCollection services)
{
services
.AddDbContext<OurContext>(options =>
options.UseSqlServer(Configuration["ConnectionString"]))
.AddDbContext<OurContext>()
.AddRazorPages()
.AddMvcOptions(options => options.EnableEndpointRouting = false)
.AddNewtonsoftJson(options => options.SerializerSettings.ContractResolver = new DefaultContractResolver());
services
.AddControllersWithViews();
//ATTEMPTED
//services
// .AddAutoMapper(AppDomain.CurrentDomain.GetAssemblies());
//ATTEMPTED
//MapperConfiguration mapperConfiguration = new MapperConfiguration(mc =>
//{
// mc.AddProfile(new OurProfile());
//});
//IMapper mapper = mapperConfiguration.CreateMapper();
//services
// .AddSingleton(mapper);
//ATTEMPTED
//services
// .AddAutoMapper(typeof(Startup));
//ATTEMPTED
//var assembly = typeof(Program).GetTypeInfo().Assembly;
//services
// .AddAutoMapper(assembly);
//ATTEMPTED
var assembly = typeof(Program).GetTypeInfo().Assembly;
services.AddAutoMapper(cfg =>
{
cfg.AllowNullDestinationValues = true;
cfg.CreateMap<OurModel, OurDto>()
.IgnoreAllPropertiesWithAnInaccessibleSetter();
}, assembly);
}
Controller
This is our controller.
[Route("api/[controller]")]
[ApiController]
public class OurController : ControllerBase
{
private readonly OurContext _context;
protected readonly ILogger<OurController> Logger;
private readonly IMapper _mapper;
public OurController(OurContext context, ILogger<OurController> logger,
IMapper mapper)
{
_context = context ??
throw new ArgumentNullException(nameof(context));
Logger = logger ??
throw new ArgumentNullException(nameof(logger));
_mapper = mapper ??
throw new ArgumentNullException(nameof(mapper));
}
[HttpGet]
public async Task<ActionResult<IEnumerable<OurDto>>> GetAll()
{
IQueryable<OurModel> models = _context.OurModel;
IQueryable<OurDto> dtos =
_mapper.Map<IQueryable<OurDto>>(models);
return await dtos.ToListAsync();
}
}
Profile, Model, and DTO
Profile
public class OurProfile : Profile
{
public OurProfile()
{
CreateMap<OurModel, OurDto>();
}
}
Model
public partial class OurModel
{
public string Number { get; set; }
public string Name1 { get; set; }
public string Name2 { get; set; }
public string Status { get; set; }
public DateTime? Date { get; set; }
public string Description { get; set; }
public string Comment { get; set; }
public string District { get; set; }
}
DTO
public class OurDto
{
public string Number { get; set; }
public string Name1 { get; set; }
public string Name2 { get; set; }
public string Status { get; set; }
public DateTime? Date { get; set; }
public string Description { get; set; }
public string Comment { get; set; }
public string District { get; set; }
}
Test Fixture
This is our test fixture.
public abstract class ApiClientFixture : IClassFixture<WebApplicationFactory<Startup>>
{
private readonly WebApplicationFactory<Startup> _factory;
protected abstract string RelativeUrl { get; }
protected ApiClientFixture(WebApplicationFactory<Startup> factory)
{
_factory = factory;
}
protected HttpClient CreateClient()
{
HttpClient client;
var builder = new UriBuilder();
client = _factory.CreateClient();
builder.Host = client.BaseAddress.Host;
builder.Path = $"{RelativeUrl}";
client.BaseAddress = builder.Uri;
return client;
}
}
Test
This is our test class. The single test in this test class fails.
public class Tests : ApiClientFixture
{
public Tests(WebApplicationFactory<Startup> factory) : base(factory)
{
}
protected override string RelativeUrl => "api/OurController/";
[Fact]
public async void GetAllReturnsSomething()
{
var response = await CreateClient().GetAsync("");
Assert.True(response.IsSuccessStatusCode);
}
}
When I debug the test I see that a 500 status code is returned from the URL provided to the in-memory API.
Does anybody have some suggestions? More than half of our tests currently fail, and I suspect that AutoMapper is not configured properly for integration testing.
Creating a map for IQueryable<T> is not really a good solution. In your answer you are losing proper flow of asynchronous database querying. I wrote about IQueryable<T> in a comment because you were looking for a 500 error cause. Making it work it's a one thing, making it a good solution it's another thing, however.
I'd strongly suggest to use AutoMapper ProjectTo() extension which you can use directly on a IQueryable<T> sequence. It let's you combine mapping and querying in one go. More or less it does a Select() based on your mappings, so it not only gives you proper model right away with the query result, but it also reduces the amount of columns obtained from database, which can make the query run faster. But, there are of course limitations to it, e.g. you can't use custom type converters or conditional mapping. You can read more about Project() in the documentation.
Usage:
public async Task<ActionResult<List<OurDto>>> GetAll()
{
return await _context
.OurModel
.ProjectTo<OutDto>(_mapper.ConfigurationProvider)
.ToListAsync();
}
Thanks to #Prolog for his comment. I realized that I need to map each element of the IQueryable individually, so I rewrote my Controller method.
Also, side note: IList.AsQueryable().ToListAsync() does not work, so I wrote:
IQueryable<OurDto> dtosQueryable = dtos.AsQueryable();
return await Task.FromResult(dtosQueryable.ToList());
Old Controller Method
[HttpGet]
public async Task<ActionResult<IEnumerable<OurDto>>> GetAll()
{
IQueryable<OurModel> models = _context.OurModel;
IQueryable<OurDto> dtos =
_mapper.Map<IQueryable<OurDto>>(models);
return await dtos.ToListAsync();
}
New Controller Method
public async Task<ActionResult<IEnumerable<OurDto>>> GetAll()
{
IQueryable<OurModel> models = _context.OurModel;
IList<OurDto> dtos = new List<OurDto>();
foreach (OurModel model in models)
{
OurDto dto = _mapper.Map<OurDto>(model);
dtos.Add(dto);
}
IQueryable<OurDto> dtosQueryable = dtos.AsQueryable();
return await Task.FromResult(dtosQueryable.ToList());
}
I have found myself with at little problem, and I think a custom model binder is the way to go.
My Domain model looks like this,readly standard
I got a Page and a Template. The Page has the Template as a ref.
So the Default asp.net mvc Binder, does not know how to bind it, therefore I need to make some rules for it. (Custom Model Binder)
public class PageTemplate
{
public virtual string Title { get; set; }
public virtual string Content { get; set; }
public virtual DateTime? Created { get; set; }
public virtual DateTime? Modified { get; set; }
}
public class Page
{
public virtual string Title { get; set; }
public virtual PageTemplate Template { get; set; }
public virtual string Content { get; set; }
public virtual DateTime? Created { get; set; }
public virtual DateTime? Modified { get; set; }
}
So I have Registreted the ModelBinder in globals.asax
ModelBinders.Binders.Add(typeof(Cms.Domain.Entities.Page),
new Cms.UI.Web.App.ModelBinders.PageModelBinder(
new Services.GenericApplicationService<Cms.Domain.Entities.Page>().GetEntityStore()
)
);
My ModelBinder tage a paremeter, witch is my Repository, where I get all my Entities ( Page, Template )
My Controller for a Page looks like this.
I have posted into a Create Controler, it does not matter for now, if it was a Update method.
Since I in this case have a dropdown, that represents the Template, I will get an ID in my form collection.
I then call: TryUpdateModel and I got a hit in my PageModelBinder.
[AcceptVerbs(HttpVerbs.Post), ValidateAntiForgeryToken]
[ValidateInput(false)]
public ActionResult Create(FormCollection form)
{
Page o = new Page();
string[] exclude = new { "Id" }
if (base.TryUpdateModel<Page>(o, string.Empty, null, exclude, form.ToValueProvider()))
{
if (ModelState.IsValid)
{
this.PageService.Add(o);
this.CmsViewData.PageList = this.PageService.List();
this.CmsViewData.Messages.AddMessage("Page is updated.", MessageTypes.Succes);
return View("List", this.CmsViewData);
}
}
return View("New", this.CmsViewData);
}
So I end op with the Model Binder.
I have search the internet dry for information, but im stock.
I need to get the ID from the FormCollection, and parse it to at Model from my IEntityStore.
But how ?
public class PageModelBinder : IModelBinder
{
public readonly IEntityStore RepositoryResolver;
public PageModelBinder(IEntityStore repositoryResolver)
{
this.RepositoryResolver = repositoryResolver;
}
public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
{
if (bindingContext == null)
{
throw new ArgumentNullException("bindingContext");
}
if (modelType == typeof(Cms.Domain.Entities.Page))
{
// Do some magic
// Get the Id from Property and bind it to model, how ??
}
}
}
// Dennis
I hope, my problom is clear.
Did find a work around.
I download the sourcecode for asp.net r2 rtm 2
And did copy all code for the default ModelBinder, and code it need. Did some minor change, small hacks.
the work around is doing a little hack in this method:
[SuppressMessage("Microsoft.Globalization", "CA1304:SpecifyCultureInfo", MessageId = "System.Web.Mvc.ValueProviderResult.ConvertTo(System.Type)",
Justification = "The target object should make the correct culture determination, not this method.")]
[SuppressMessage("Microsoft.Design", "CA1031:DoNotCatchGeneralExceptionTypes",
Justification = "We're recording this exception so that we can act on it later.")]
private static object ConvertProviderResult(ModelStateDictionary modelState, string modelStateKey, ValueProviderResult valueProviderResult, Type destinationType)
{
try
{
object convertedValue = valueProviderResult.ConvertTo(destinationType);
return convertedValue;
}
catch (Exception ex)
{
try
{
// HACK if the binder still fails, try get the entity in db.
Services.GenericApplicationService<Cms.Domain.Entities.PageTemplate> repo;
repo = new Services.GenericApplicationService<Cms.Domain.Entities.PageTemplate>();
int id = Convert.ToInt32(valueProviderResult.AttemptedValue);
object convertedValue = repo.Retrieve(id);
return convertedValue;
}
catch (Exception ex1)
{
modelState.AddModelError(modelStateKey, ex1);
return null;
}
}
}
This question is closed.
I have a parent object book, and a property of that object is publisher. Everytime I ad a book, it is adding a new publisher, even if the publisher already exists. Can someone tell me how to add the book and instead of adding the publisher again, just reference an existing one? The code i am using is below... Thanks in advance!
public class Book
{
public int BookID { get; set; }
public string Title { get; set; }
public string Description { get; set; }
public DateTime CreateDate { get; set; }
public virtual Publisher Publisher { get; set; }
}
public class Publisher
{
public int PublisherID { get; set; }
public string Address { get; set; }
}
public class SqlCEDataStore : DbContext
{
public DbSet<Book> Books { get; set; }
public DbSet<Publishers> Publishers { get; set; }
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.IncludeMetadataInDatabase = false;
}
}
public class TimeSinkRepository : IRepository<Book>
{
private static SqlCEDataStore context = new SqlCEDataStore();
public int Add(Book entity)
{
context.Books.Add(entity);
return context.SaveChanges();
}
}
var book = new Book()
{
Title = "New Title",
Description = "New Description",
CreateDate = DateTime.Now,
Publisher = new Publisher() { PublisherID = 1 }
};
var repository = new BookRepository();
var result = repository.Add(book);
The problem is in the line:
Publisher = new Publisher() { PublisherID = 1 }
Object context doesn't know that this is existing publisher. It is newly created entity so Object context will perform insert operation. You have to say object context that the publisher object is not newly created. One way to do that is modification of your Add method:
public int Add(Book entity)
{
context.Books.Add(entity);
// 0 means new one, other values mean existing one
if (entity.Publisher.PublisherID > 0)
{
context.ObjectStateManager.ChangeObjectState(entity.Publisher, EntityState.Unchanged);
}
context.SaveChanges();
}
It you can solve this by making sure the Publisher is attached to Publishers context before adding the Book entity (this way it knows it's a Publisher from the dbcontext and not a new one that it needs to add (again))
context.Publishers.Attach(book.Publisher); // This is only possible if the Publisher is not new
context.Books.Add(book);
the problem is in this line
Publisher = new Publisher() { PublisherID = 1 }
You should do a fetch method so something like this
- Get the Publisher you want from the context (eg where id = 1)
- Set the returned object as the publisher for your new book object
- The context should sort the rest out for you. when you save the book. (no need to mess with the object state manager)
Good luck, if you cant get this working put up some code of it and i will help you though it.