仅在 IIS 中发布时，在 ASP.net Core 3.1 WebAPI 中启用 CORS 时出错

Question

我有一个带有 asp core 3.1 的 api 当我使用本地主机时，一切都很好，但是当我在我的 IIS 上发布它时它不起作用并给我启用 CORS 的错误

我的 startup.cs 代码是

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

    public IConfiguration Configuration { get; }

    // This method gets called by the runtime. Use this method to add services to the container.
    public void ConfigureServices(IServiceCollection services)
    {



        services.AddDbContext<ApplicationDbContext>(
        options => options.UseSqlServer(
            this.Configuration.GetConnectionString("DefaultConnection")));

        //Configure Identity framework core  
        services.AddIdentityCore<ApplicationUser>()
             .AddEntityFrameworkStores<ApplicationDbContext>().AddDefaultTokenProviders();



        services.AddIdentity<ApplicationUser, IdentityRole>(config =>
        {
            config.Password.RequiredLength = 4;
            config.Password.RequireDigit = false;
            config.Password.RequireNonAlphanumeric = false;
            config.Password.RequireUppercase = false;
            config.Password.RequireLowercase = false;
        })
           .AddEntityFrameworkStores<ApplicationDbContext>()
           .AddDefaultTokenProviders();




        services.AddCors(options =>
        {
            options.AddPolicy("CrosPolicy", builder =>
            builder
            .SetIsOriginAllowed((host) => true)
            //.AllowAnyOrigin()
            .AllowAnyMethod()
            .AllowAnyHeader()
            .AllowCredentials()
            .Build()
            );
        });
        services.AddControllers();

        services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
            .AddJwtBearer(options =>
           {
               options.TokenValidationParameters = new TokenValidationParameters
               {
                   ValidateIssuer = true,
                   ValidateAudience = true,
                   ValidateLifetime = true,
                   ValidateIssuerSigningKey = true,
                   ValidIssuer = Configuration["jwt:Issuer"],
                   ValidAudience = Configuration["jwt:Issuer"],
                   IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(Configuration["jwt:key"]))
               };
           });            

    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }

        app.UseHttpsRedirection();

        app.UseRouting();

        app.UseCors("CrosPolicy");

        app.UseAuthentication();

        app.UseAuthorization();

        app.UseEndpoints(endpoints =>
        {
            endpoints.MapControllers();
        });
    }
}

我不知道我要做什么请帮助我，我也在这篇文章中尝试解决方案，How to enable CORS in ASP.net Core WebAPI 它不适合我

Answer 1

我尝试了很多东西，但最后我找到了解决方案，我像这样改变了 CORS 的位置：

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

    public IConfiguration Configuration { get; }

    public void ConfigureServices(IServiceCollection services)
    {



        services.AddDbContext<ApplicationDbContext>(
        options => options.UseSqlServer(
            this.Configuration.GetConnectionString("DefaultConnection")));


        services.AddIdentityCore<ApplicationUser>()
             .AddEntityFrameworkStores<ApplicationDbContext>().AddDefaultTokenProviders();



        services.AddIdentity<ApplicationUser, IdentityRole>(config =>
        {
            config.Password.RequiredLength = 4;
            config.Password.RequireDigit = false;
            config.Password.RequireNonAlphanumeric = false;
            config.Password.RequireUppercase = false;
            config.Password.RequireLowercase = false;
        })
           .AddEntityFrameworkStores<ApplicationDbContext>()
           .AddDefaultTokenProviders();




        services.AddControllers();

        services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
            .AddJwtBearer(options =>
           {
               options.TokenValidationParameters = new TokenValidationParameters
               {
                   ValidateIssuer = true,
                   ValidateAudience = true,
                   ValidateLifetime = true,
                   ValidateIssuerSigningKey = true,
                   ValidIssuer = Configuration["jwt:Issuer"],
                   ValidAudience = Configuration["jwt:Issuer"],
                   IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(Configuration["jwt:key"]))
               };
           });


        services.AddMvc();

    }


    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }

        app.UseHttpsRedirection();

        app.UseRouting();

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

        app.UseAuthentication();

        app.UseAuthorization();

        app.UseEndpoints(endpoints =>
        {
            endpoints.MapControllers();
        });
    }