被 CORS 策略阻止：No 'Access-Control-Allow-Origin in .netCore7 Web Api

Question

后端项目我使用了.net core 7.0 我还在用户端使用了 React 我按照文档进行了所有设置。但我得到一个错误： 从来源“http://x.x.x.x:1400”访问位于“http://x.x.x.x:1402/api/auth/login”的 XMLHttpRequest 已被 CORS 策略阻止：不存在“Access-Control-Allow-Origin”标头在请求的资源上。 我的 Startup.cs 类：

  public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }



        public void ConfigureServices(IServiceCollection services)
        {


            // Add for Remove null fields from API JSON response
            services.AddMvc()
            .AddJsonOptions(options =>
            {
                options.JsonSerializerOptions.DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull;
            });

            // AddAutoMapper
            services.AddAutoMapper(typeof(Startup));

            services.AddControllers(config =>
            {
                config.Filters.Add(new ApiExceptionFilter());
                config.Filters.Add(new ApiActionFilter());
                config.Filters.Add(new ApiResultFilter());
            });

            ServiceRegistration.AddInfrastructure(services);

            string key = "xxxxxxxxxx";
            services.AddAuthentication(x =>
            {
                x.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
                x.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
            }).AddJwtBearer(x =>
            {
                x.RequireHttpsMetadata = false;
                x.SaveToken = true;
                x.TokenValidationParameters = new Microsoft.IdentityModel.Tokens.TokenValidationParameters
                {
                    ValidateIssuerSigningKey = true,
                    ValidateIssuer = false,
                    ValidateAudience = false,
                    IssuerSigningKey = new SymmetricSecurityKey(Encoding.ASCII.GetBytes(key)),
                    ValidAudience = Configuration["Tokens:Audience"],
                    ValidIssuer = Configuration["Tokens:Issuer"],
                    ValidateLifetime = true,
                    ClockSkew = TimeSpan.Zero
                };
            });

            services.AddSingleton<IJwtAuth>(new Auth.Auth(key));
            services.AddSwaggerGen(c =>
            {
     
                OpenApiSecurityScheme jwtSecurityScheme = new OpenApiSecurityScheme
                {
                    Scheme = "bearer",
                    BearerFormat = "JWT",
                    Name = "JWT Authentication",
                    In = ParameterLocation.Header,
                    Type = SecuritySchemeType.Http,
                   
                    Reference = new OpenApiReference
                    {
                        Id = JwtBearerDefaults.AuthenticationScheme,
                        Type = ReferenceType.SecurityScheme
                    }
                };
                c.SwaggerDoc("v1", new OpenApiInfo
                {
                    Version = "v1",
                });
                c.AddSecurityDefinition(jwtSecurityScheme.Reference.Id, jwtSecurityScheme);
                c.AddSecurityRequirement(new OpenApiSecurityRequirement
                {
                    { jwtSecurityScheme, Array.Empty<string>() }
                });


                string xmlFilename = $"{Assembly.GetExecutingAssembly().GetName().Name}.xml";
                c.IncludeXmlComments(Path.Combine(AppContext.BaseDirectory, xmlFilename));

            });
        }


        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            // My Custom Middleware
            app.UseMainMiddleware();

            app.UseCors(
                options => options
                        .AllowAnyMethod()
                        .AllowAnyHeader()
                        .AllowAnyOrigin()
            );


            app.UseHttpsRedirection();
            app.UseAuthentication();
            app.UseRouting();
            app.UseAuthorization();
            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllers();
            });

            //app.UseMvc();

        }

    }