我已经启用了cors的原点，但仍未获得访问权限控制。

Question

我用角度作为前端。正在要求Web API核心项目中的API响应。由于两者都在不同的来源上运行，因此我已经设置了交叉来源资源共享，但仍会出现错误，没有“访问控制 - 允许 - 孔” ............................................................................................................................................................................................................................................................................................................................................................. ................................................................................. .....

​

using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.HttpsPolicy;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using Microsoft.OpenApi.Models;
using pizzaria.Model;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace pizzaria
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {

            services.AddControllers();
            services.AddDbContext<databaseContext>(db => db.UseSqlServer(Configuration.GetConnectionString("Connection")));
            services.AddSwaggerGen(c =>
            {
                c.SwaggerDoc("v1", new OpenApiInfo { Title = "pizzaria", Version = "v1" });
            });
            services.AddCors(cors => cors.AddPolicy("MyPolicy", builder => {
                builder.WithOrigins("http://localhost:4200").AllowAnyMethod().AllowAnyHeader();
            }));

        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
                app.UseSwagger();
                app.UseSwaggerUI(c => c.SwaggerEndpoint("/swagger/v1/swagger.json", "pizzaria v1"));
            }
            app.UseAuthentication();
            app.UseHttpsRedirection();

            app.UseRouting();

            app.UseCors("MyPolicy");
            app.UseAuthorization();

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllers();
            });

          
        }
    }
}

​

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Cors;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using pizzaria.Model;

namespace pizzaria.Controllers
{
    [EnableCors("http://localhost:4200,*,*")]
    [Route("api/[controller]")]
    [ApiController]
    public class UserAccountsController : ControllerBase
    {
        private readonly databaseContext _context;
       
        public UserAccountsController(databaseContext context)
        {
            _context = context;
        }
     
        // GET: api/UserAccounts
        [HttpGet]
        public async Task<ActionResult<IEnumerable<UserAccount>>> GetuserAccounts()
        {
            return await _context.userAccounts.ToListAsync();
        }

        // GET: api/UserAccounts/5
        [HttpGet("{id}")]
        public async Task<ActionResult<UserAccount>> GetUserAccount(string id)
        {
            var userAccount = await _context.userAccounts.FindAsync(id);

            if (userAccount == null)
            {
                return NotFound();
            }

            return userAccount;
        }

        // PUT: api/UserAccounts/5
        // To protect from overposting attacks, see https://go.microsoft.com/fwlink/?linkid=2123754
        [HttpPut("{id}")]
        public async Task<IActionResult> PutUserAccount(string id, UserAccount userAccount)
        {
            if (id != userAccount.userId)
            {
                return BadRequest();
            }

            _context.Entry(userAccount).State = EntityState.Modified;

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!UserAccountExists(id))
                {
                    return NotFound();
                }
                else
                {
                    throw;
                }
            }

            return NoContent();
        }

        // POST: api/UserAccounts
        // To protect from overposting attacks, see https://go.microsoft.com/fwlink/?linkid=2123754
        [HttpPost]
        public async Task<ActionResult<UserAccount>> PostUserAccount(UserAccount userAccount)
        {
            _context.userAccounts.Add(userAccount);
            await _context.SaveChangesAsync();

            return CreatedAtAction("GetUserAccount", new { id = userAccount.userId }, userAccount);
        }

        // DELETE: api/UserAccounts/5
        [HttpDelete("{id}")]
        public async Task<IActionResult> DeleteUserAccount(string id)
        {
            var userAccount = await _context.userAccounts.FindAsync(id);
            if (userAccount == null)
            {
                return NotFound();
            }

            _context.userAccounts.Remove(userAccount);
            await _context.SaveChangesAsync();

            return NoContent();
        }

        private bool UserAccountExists(string id)
        {
            return _context.userAccounts.Any(e => e.userId == id);
        }
    }
}

​

import { Component, OnInit } from '@angular/core';
import { HttpClient } from '@angular/common/http';

@Component({
  selector: 'app-signin',
  templateUrl: './signin.component.html',
  styleUrls: ['./signin.component.css']
})
export class SigninComponent implements OnInit {
  li: any;
  lis = [];
  constructor(private http: HttpClient) { }

  ngOnInit(): void {

    console.log("started");
    this.http.get("https://localhost:44302/api/userAccounts").subscribe(Response => {

      // If response comes hideloader() function is called
      // to hide that loader
      console.log("working");
      if (Response) {
        console.log("working");
      }
      console.warn("not working")
      this.li = Response;
      this.lis = this.li.list;
    });

    console.warn("function exit");
  }

}
```[enter image description here][1]


  [1]: https://i.sstatic.net/TcUFw.jpg

Answer 1

尝试将其更改为

            services.AddCors(cors => cors.AddPolicy(name: MyPolicy, builder => {builder.WithOrigins("http://localhost:4200").AllowAnyMethod().AllowAnyHeader();
            }));

.
.
.
            app.UseCors(MyPolicy);

我认为您不应该使用双引号标记