Blazor WebAssembly with identity server passing username through form - asp.net

Question

I am new to Blazor WebAssembly. I have a simple page that allows users to register a company. It takes the company name, description and the username. At the moment the username is entered by the user but I want to automatically grab the username of the logged in user and post it without the need of user input. Here is my page:
#page "/companies/create"
#attribute [Authorize]
#inject HttpClient Http
#inject NavigationManager Navigation
<h3>Register your company</h3>
<AuthorizeView>
Hello, #context.User.Identity.Name!
</AuthorizeView>
<EditForm Model="Companies" OnValidSubmit="#HandleValidSubmit">
<DataAnnotationsValidator />
<div class="form-group">
<label class="control-label">Name</label>
<InputText #bind-Value="Companies.Name" class="form-control" />
<ValidationMessage For="#(() => Companies.Name)" />
</div>
<div class="form-group">
<label class="control-label">Description</label>
<InputText #bind-Value="Companies.Description" class="form-control" />
<ValidationMessage For="#(() => Companies.Description)" />
</div>
<div class="form-group">
<label class="control-label">Username</label>
<InputText #bind-Value="Companies.Username" class="form-control"/>
<ValidationMessage For="#(() => Companies.Username)" />
</div>
<button type="submit" class="btn btn-primary">
<i class="fas fa-save"></i> Register
</button>
</EditForm>
#code {
private Sprelo.Shared.Companies Companies { get; set; } = new Sprelo.Shared.Companies();
private async void HandleValidSubmit()
{
try
{
var response = await Http.PostAsJsonAsync($"/api/companies", Companies);
response.EnsureSuccessStatusCode();
var content = await response.Content.ReadAsStringAsync();
var companies = JsonConvert.DeserializeObject<Sprelo.Shared.Companies>(content);
Navigation.NavigateTo($"Companies/edit/{companies.Id}");
}
catch (AccessTokenNotAvailableException exception)
{
exception.Redirect();
}
catch (Exception e)
{
}
}
}
This is my model:
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Sprelo.Shared
{
public class Companies
{
[Key]
public Guid Id { get; set; }
[Required]
public String Name { get; set; }
public String Description { get; set; }
public String Username { get; set; }
}
}
and this is an auto generated API controller
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Sprelo.Server.Data;
using Sprelo.Shared;
namespace Sprelo.Server.Controllers
{
[Route("api/[controller]")]
[ApiController]
public class CompaniesController : ControllerBase
{
private readonly ApplicationDbContext _context;
public CompaniesController(ApplicationDbContext context)
{
_context = context;
}
// GET: api/Companies
[HttpGet]
public async Task<ActionResult<IEnumerable<Companies>>> GetCompanies()
{
return await _context.Companies.ToListAsync();
}
// GET: api/Companies/5
[HttpGet("{id}")]
public async Task<ActionResult<Companies>> GetCompanies(Guid id)
{
var companies = await _context.Companies.FindAsync(id);
if (companies == null)
{
return NotFound();
}
return companies;
}
// PUT: api/Companies/5
// To protect from overposting attacks, see https://go.microsoft.com/fwlink/?linkid=2123754
[HttpPut("{id}")]
public async Task<IActionResult> PutCompanies(Guid id, Companies companies)
{
if (id != companies.Id)
{
return BadRequest();
}
_context.Entry(companies).State = EntityState.Modified;
try
{
await _context.SaveChangesAsync();
}
catch (DbUpdateConcurrencyException)
{
if (!CompaniesExists(id))
{
return NotFound();
}
else
{
throw;
}
}
return NoContent();
}
// POST: api/Companies
// To protect from overposting attacks, see https://go.microsoft.com/fwlink/?linkid=2123754
[HttpPost]
public async Task<ActionResult<Companies>> PostCompanies(Companies companies)
{
_context.Companies.Add(companies);
await _context.SaveChangesAsync();
return CreatedAtAction("GetCompanies", new { id = companies.Id }, companies);
}
// DELETE: api/Companies/5
[HttpDelete("{id}")]
public async Task<IActionResult> DeleteCompanies(Guid id)
{
var companies = await _context.Companies.FindAsync(id);
if (companies == null)
{
return NotFound();
}
_context.Companies.Remove(companies);
await _context.SaveChangesAsync();
return NoContent();
}
private bool CompaniesExists(Guid id)
{
return _context.Companies.Any(e => e.Id == id);
}
}
}
I have been struggling with this for quite a while, any help would be appriciated!

Answer 1

Inject the AuthenticationStateProvider object into your component like this:
#inject AuthenticationStateProvider authProvider
Override the OnInitialized life cycle method:
protected override void OnInitialized ()
{
var authenticationStateTask = await
authProvider.GetAuthenticationStateAsync();
var user = authenticationStateTask.User;
// Check if the user is authenticated
if (user.Identity.IsAuthenticated)
{
// Grab the user name and assign it to Companies.Username
Companies.Username = user.Identity.Name
}
}