如何在asp.net自托管API中启用CORS？

Question

I created one self-hosted Web API in asp.net it works fine when I call it from POSTMAN but it gives below error when I invoke it from browser.

Access to XMLHttpRequest at ' http://localhost:3273/Values/GetString/1 ' from origin ' http://localhost:4200 ' has been blocked by CORS policy: No 'Access-Control-A

Below given is my service class

using System.Web.Http;
using System.Web.Http.SelfHost;

namespace SFLSolidWorkAPI
{
    public partial class SolidWorkService : ServiceBase
    {
        public SolidWorkService()
        {
            InitializeComponent();
        }

        protected override void OnStart(string[] args)
        {
            var config = new HttpSelfHostConfiguration("http://localhost:8069");


            config.Routes.MapHttpRoute(
               name: "API",
               routeTemplate: "{controller}/{action}/{id}",
               defaults: new { id = RouteParameter.Optional }
           );

            HttpSelfHostServer server = new HttpSelfHostServer(config);
            server.OpenAsync().Wait();
        }

        protected override void OnStop()
        {
        }
    }

}

Answer 1

Here,

I found solution for this problem after so many research. You just need to install Microsoft.AspNet.WebApi.Cors and use it like config.EnableCors(new EnableCorsAttribute("*", headers: "*", methods: "*"));

Hope it will help others.

Thanks

using System;
using System.ServiceProcess;
using System.Web.Http;
using System.Web.Http.Cors;
using System.Web.Http.SelfHost;

namespace SFLSolidWorkAPI
{
    public partial class DemoService : ServiceBase
    {
        public DemoService ()
        {
            InitializeComponent();
        }

        protected override void OnStart(string[] args)
        {
            var config = new HttpSelfHostConfiguration("http://localhost:8069");


            config.Routes.MapHttpRoute(
               name: "API",
               routeTemplate: "{controller}/{action}/{id}",
               defaults: new { id = RouteParameter.Optional }
           );
            config.EnableCors(new EnableCorsAttribute("*", headers: "*", methods: "*"));

            HttpSelfHostServer server = new HttpSelfHostServer(config);
            server.OpenAsync().Wait();
        }

        protected override void OnStop()
        {
        }
    }

}