While working my EF core Application I was getting this exception message. I fixed this issue like this
Step 1: In Insert/update method make ensure to detach the entity.
_db.Entry(localRopFiles).State = EntityState.Detached;Step 2: If you are loading data on page load then use AsNoTracking() method
var query = await _db.LocalRopFiles.AsNoTracking().ToListAsync();
I hope this will help some one who is getting this type of exception.
Here is the syntax for calling taken based web api in Blazor server or webassembly.
using MyFleetApp.Data.Model;
using System.Net.Http;
using System.Net.Http.Json;
using System.Threading.Tasks;
namespace MyFleetApp.Data.Service
{
public class InvoiceSearchService : IInvoiceSerach
{
private readonly HttpClient httpClient;
public InvoiceSearchService(HttpClient httpClient)
{
this.httpClient = httpClient;
}
public async Task<Rootobject> GetInvoices(Rootobject objParameter)
{
httpClient.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", objParameter.token);
var result = await httpClient.PostAsJsonAsync<Rootobject>("Web API URL will be here", objParameter);
Rootobject objInvoice = new Rootobject();
if (result.IsSuccessStatusCode)
{
objInvoice = await result.Content.ReadFromJsonAsync<Rootobject>();
}
return objInvoice;
}
}
}
While designing any form we will get requirement of legend tag for good look and feel. We can design the form using bootstrap 4 and legend like this
<fieldset class="border p-2">
<legend class="w-auto">
Fleet Search
</legend>
</fieldset>If we have to format the Nullable Date in C#, We can do like this
DateTime? date = new DateTime(2021, 05, 10, 22, 45, 12, 004);
//Will through exception
// string date_str = date.ToString("dd/MM/yyyy");
//Working Syntax:
string date_str= (date != null ? date.Value.ToString("dd/MM/yyyy") : "n/a");
Chandradev's Blog 