Post IIS拦截飞行前MVC6

我正在尝试启用CORS，允许我的angular应用程序与新的MVC6 Web Api对话

“GET”有效，但“POST”无效，因为CORS飞行前先发送。IIS拦截此预飞行并作出响应

在WebApi2中，我能够使用以下web.config设置阻止IIS拦截预飞行

<configuration>
  <system.webServer>
    <handlers>
      <remove name="ExtensionlessUrlHandler-Integrated-4.0" />
      <remove name="OPTIONSVerbHandler" />
      <remove name="TRACEVerbHandler" />
      <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="GET, HEAD, POST, DEBUG, DELETE, PUT, PATCH, OPTIONS" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />
    </handlers>
  </system.webServer>
</configuration>

我可以在新的MVC6 WebApi中完成这两项工作，但由于某些原因，我无法让IIS停止拦截“选项”飞行前

我在MVC中使用了这段代码，我相信如果我只能让IIS停止拦截“选项”请求，它就会起作用

有没有人处理过这个问题，或者有一个MVC6和CORS一起工作的例子

---

谢谢

我建议一个工作正常的人：

app.Use(async (context, next) =>
{
    context.Response.Headers.Add("Access-Control-Allow-Origin", "*");
    context.Response.Headers.Add("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS");
    context.Response.Headers.Add("Access-Control-Allow-Headers", new[] { "Content-Type, x-xsrf-token" });

    if (context.Request.Method == "OPTIONS")
    {
        context.Response.StatusCode = 200;
    }
    else
    {
        await next();
    }
});

---

如果有人想下载并试一试，我已经在GitHub上创建了一个回购协议。您将需要Visual Studio 2015。复制

        app.Use(async (httpContext, next) =>
        {
            httpContext.Response.OnSendingHeaders((state) =>
            {

                if (httpContext.Request.Path.Value.Contains("api/") && httpContext.Request.Method == "OPTIONS")
                {
                    httpContext.Response.Headers.Add("Access-Control-Allow-Origin", new[] { httpContext.Request.Headers["Origin"] });
                    httpContext.Response.Headers.Add("Access-Control-Allow-Headers", new[] { "Origin, X-Requested-With, Content-Type, Accept" });
                    httpContext.Response.Headers.Add("Access-Control-Allow-Methods", new[] { "GET, POST, PUT, DELETE, OPTIONS" });
                    httpContext.Response.Headers.Add("Access-Control-Allow-Credentials", new[] { "true" });
                    return;
                }
            }, null);

            await next();

        });

app.Use(async (context, next) =>
{
    context.Response.Headers.Add("Access-Control-Allow-Origin", "*");
    context.Response.Headers.Add("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS");
    context.Response.Headers.Add("Access-Control-Allow-Headers", new[] { "Content-Type, x-xsrf-token" });

    if (context.Request.Method == "OPTIONS")
    {
        context.Response.StatusCode = 200;
    }
    else
    {
        await next();
    }
});