User379720387 posted
I need help with understanding how I can present data from related Entities in Blazor Server.
The current state of the my art is that I can present data from a single Entity on my razor page, with data coming from controllers inside the Api project which also has the EF Core Model.
The operative sections of code:
public DbSet<Transaction> Transactions { get; set; } (in AppDbContext)
[HttpGet]
public async Task<ActionResult<List<Transaction>>> Get() => await context.Transactions
.OrderByDescending(t => t.TransactionId)
.ToListAsync();
BtServer.Transaction[] transactions;
protected async override Task OnInitializedAsync()
{
var httpClient = ClientFactory.CreateClient("ServerApi");
httpClient.BaseAddress = new Uri(@"https://localhost:44317/");
httpClient.DefaultRequestHeaders.Add("Accept", "application/json");
transactions = await httpClient.GetFromJsonAsync<BtServer.Transaction[]>("api/Transaction");
}
VS tells me the blue highlighted Transaction in TransactionController is BtApiCore.Model.Transaction, that is the Entity Model for Transaction.cs created during the scaffolding. Which I understand.
The green highlighted Transaction is BtServer.Transaction, which is interesting because there is no class called Transaction in the BtServer project. Thoughts?
Moving past that, I am thinking this is somehow pointing to Transaction.cs the model that EF Core created during the scaffolding. Correct me if I am wrong please.
The above all works.
My next task is to figure out how I can get some of the Transaction foreign relationship to resolve.
Created a ProviderTransaction model that lives in the Model folder in BtApiCore project, alongside with the Entity models.
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Threading.Tasks;
namespace BtApiCore.Model
{
public class ProviderTransaction
{
[Key] public int TransactionId { get; set; }
public string Location { get; set; }
public string OName { get; set; }
public string State { get; set; }
public string CName { get; set; }
public int BillNo { get; set; }
public bool IsBilled { get; set; }
public string Service { get; set; }
public decimal Charge { get; set; }
public decimal Tax { get; set; }
public DateTime TDate { get; set; }
public DateTime BDate { get; set; }
public bool IsPaid { get; set; }
public virtual Client Client { get; set; }
public virtual LocationTxRate Ltr { get; set; }
[ForeignKey("OwnerBillToId")]
public virtual Owner OwnerBillTo { get; set; }
[ForeignKey("OwnerLocationId")]
public virtual Owner OwnerLocation { get; set; }
public virtual Property Property { get; set; }
public virtual Provider Provider { get; set; }
public virtual ServiceLevel Sl { get; set; }
}
}
public DbSet<ProviderTransaction> ProviderTransactions { get; set; }
[HttpGet]
public async Task<ActionResult<List<ProviderTransaction>>> Get() => await context.ProviderTransactions
.OrderByDescending(t => t.TransactionId)
.ToListAsync();
BtServer.ProviderTransaction[] providertransactions;
protected async override Task OnInitializedAsync()
{
var httpClient = ClientFactory.CreateClient("ServerApi");
httpClient.BaseAddress = new Uri(@"https://localhost:44317/");
httpClient.DefaultRequestHeaders.Add("Accept", "application/json");
providertransactions = await httpClient.GetFromJsonAsync<BtServer.ProviderTransaction[]>("api/ProviderTransaction");
}
I am thinking this should now work. :( Nope, problem with the API, below is the HttpRepl output. I am assuming it doesn't like context.ProviderTransaction highlighted yellow above.
https://localhost:44317/api> dir
. []
.. []
Breed [GET]
Client [GET]
Country [GET]
Owner [GET]
Printer [GET]
Provider [GET]
ProviderTransaction [GET]
Transaction [GET]
User [GET]
https://localhost:44317/api> Get ProviderTransaction
HTTP/1.1 500 Internal Server Error
Content-Type: text/plain
Date: Wed, 30 Dec 2020 17:10:26 GMT
Server: Microsoft-IIS/10.0
Transfer-Encoding: chunked
X-Powered-By: ASP.NET
Microsoft.Data.SqlClient.SqlException (0x80131904): Invalid object name 'ProviderTransactions'.
at Microsoft.Data.SqlClient.SqlCommand.<>c.<ExecuteDbDataReaderAsync>b__169_0(Task`1 result)
at System.Threading.Tasks.ContinuationResultTaskFromResultTask`2.InnerInvoke()
at System.Threading.Tasks.Task.<>c.<.cctor>b__277_0(Object obj)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
--- End of stack trace from previous location ---
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot, Thread threadPoolThread)
--- End of stack trace from previous location ---
at Microsoft.EntityFrameworkCore.Storage.RelationalCommand.ExecuteReaderAsync(RelationalCommandParameterObject parameterObject, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Storage.RelationalCommand.ExecuteReaderAsync(RelationalCommandParameterObject parameterObject, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Query.Internal.SingleQueryingEnumerable`1.AsyncEnumerator.InitializeReaderAsync(DbContext _, Boolean result, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.SqlServer.Storage.Internal.SqlServerExecutionStrategy.ExecuteAsync[TState,TResult](TState state, Func`4 operation, Func`4 verifySucceeded, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Query.Internal.SingleQueryingEnumerable`1.AsyncEnumerator.MoveNextAsync()
at Microsoft.EntityFrameworkCore.EntityFrameworkQueryableExtensions.ToListAsync[TSource](IQueryable`1 source, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.EntityFrameworkQueryableExtensions.ToListAsync[TSource](IQueryable`1 source, CancellationToken cancellationToken)
at BtApiCore.Controllers.ProviderTransactionController.Get() in C:\Users\Robert\source\Repos\BtApiCore\Controllers\ProviderTransactionController.cs:line 25
at lambda_method5(Closure , Object )
at Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.AwaitableObjectResultExecutor.Execute(IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeActionMethodAsync>g__Awaited|12_0(ControllerActionInvoker invoker, ValueTask`1 actionResultValueTask)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeNextActionFilterAsync>g__Awaited|10_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Rethrow(ActionExecutedContextSealed context)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeInnerFilterAsync>g__Awaited|13_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeFilterPipelineAsync>g__Awaited|19_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
at Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger)
at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
at Swashbuckle.AspNetCore.SwaggerUI.SwaggerUIMiddleware.Invoke(HttpContext httpContext)
at Swashbuckle.AspNetCore.Swagger.SwaggerMiddleware.Invoke(HttpContext httpContext, ISwaggerProvider swaggerProvider)
at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)
ClientConnectionId:9e77a8b9-f5e0-48c2-8229-2c01519905aa
Error Number:208,State:1,Class:16
HEADERS
=======
Host: localhost:44317
User-Agent: HTTP-REPL
Help me understand how this is supposed to work, please.
