set access-control-allow-origin in web api asp.net core code example

Example 1: asp.net core allow all origins

public void ConfigureServices(IServiceCollection services)
{
    services.AddCors(options =>
    {
        options.AddPolicy(MyAllowSpecificOrigins,
        builder =>
        {
            builder.WithOrigins("http://example.com",
                                "http://www.contoso.com")
                                .AllowAnyHeader()
                                .AllowAnyMethod();
        });
    });

    services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
}

Example 2: how to enable cors policy in web api

BY LOVE
To enable CORS policy in web api, You need to add this method in your Global.asax file of API project. i.e
        
        protected void Application_BeginRequest()
        {
            HttpContext.Current.Response.AddHeader("Access-Control-Allow-Origin", "*");
        }