Access to XMLHttpRequest at 'https://localhost:44363/api/Values' from origin 'http://localhost:4200' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

 Access to XMLHttpRequest at 'https://localhost:44363/api/Values' from origin 'http://localhost:4200' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

Error in .net core API of CORS add first red color line and with origins is your link of angular. and 2nd is Configure method with red color in startup class both in startup.cs.

 public void ConfigureServices(IServiceCollection services)

        {

            //services.AddCors(o => o.AddPolicy("MyPolicy", builder =>

            //{

            //    builder.AllowAnyOrigin()

            //           .AllowAnyMethod()

            //           .AllowAnyHeader()

            //           ;

            //}));

            services.AddCors(options => options.AddDefaultPolicy(builder =>

            {

                builder.WithOrigins("http://localhost:4200").AllowAnyMethod().AllowAnyHeader();

            }));

            services.AddControllers();

            services.AddSwaggerGen(c =>

            {

                c.SwaggerDoc("v1", new OpenApiInfo { Title = "WebApplication5", Version = "v1" });

            });

        }

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)

        {

            if (env.IsDevelopment())

            {

                app.UseDeveloperExceptionPage();

                app.UseSwagger();

                app.UseSwaggerUI(c => c.SwaggerEndpoint("/swagger/v1/swagger.json", "WebApplication5 v1"));

            }

        

            app.UseCors();

            app.UseHttpsRedirection();

            app.UseRouting();

            app.UseAuthorization();

            app.UseEndpoints(endpoints =>

            {

                endpoints.MapControllers();

            });

        }