No 'Access-Control-Allow-Origin' header is present on the requested

Question

Access to XMLHttpRequest at 'http://localhost:8080/api/photos/%7B_id%7D' from origin 'http://localhost:4200' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

Sachin Singh · Answer

if you are getting the issue in web api 2 then follow two steps 1.Go to tools-->package Manager Console and install following package PM> Install-Package Microsoft.AspNet.WebApi.Cors 2.Go to App_Start folder and open WebAPIConfig and add EnableCors() in the Register method. public static class WebApiConfig { public static void Register(HttpConfiguration config) { // Web API routes config.MapHttpAttributeRoutes(); config.EnableCors(); // notice here config.Routes.MapHttpRoute( name: "DefaultApi" , routeTemplate: "api/{controller}/{id}" , defaults: new { id = RouteParameter.Optional } ); }

Rijwan Ansari · Answer

Only for .NET Core Web API project, add following changes: Add the following code after the services.AddMvc() line in the ConfigureServices() method of the Startup.cs file: services.AddCors( allowsites => {allowsites.AddPolicy( "AllowOrigin" , options => options.AllowAnyOrigin()); }); Add the following code after app.UseMvc() line in the Configure() method of the Startup.cs file: app.UseCors( options => options.AllowAnyOrigin()); Open the controller which you want to access outside the domain and add this following attribute at the controller level: [EnableCors( "AllowOrigin" )]

Kiran Mohanty · Answer

You should enable CORs while accessing cross domain API. In .net Core public void ConfigureServices(IServiceCollection services) { services.AddCors(options => { options.AddPolicy( "Policy11" , builder => builder.WithOrigins( "http://hello.com" )); }); } public void Configure(IApplicationBuilder app) { app.UseCors( "AllowMyOrigin" ); } In MVC public static void Register(HttpConfiguration config) { config.EnableCors(); }

Jignesh Kumar · Answer

Hi Jegan, Please use this link which will help you to allo CORS on your api request, https://www.c-sharpcorner.com/article/enabling-cors-in-asp-net-core-api-application/ https://www.infoworld.com/article/3327562/how-to-enable-cors-in-aspnet-core.html

No 'Access-Control-Allow-Origin' header is present on the requested

Answers (4)