从IIS中删除Etag和Last-Modified标头

Question

您是否知道可以通过完全删除ETag和Last-Modifed响应头来阻止浏览器缓存中的文件重新验证以及随后的304响应？

当然,这在Apache中很容易,但在IIS 6中就像泥浆一样清晰.有谁知道如何在IIS中删除这两个头文件？

Answer 1

一种编程方式是使用HTTP模块,就像这样(基于Luke的SO答案):

namespace HttpModules
{
    using System;
    using System.Web;

    public class RemoveExtraneousHeaderModule : IHttpModule
    {
        /// <summary>
        /// Initializes a module and prepares it to handle requests.
        /// </summary>
        /// <param name="context">Provides access to the request context.</param>
        public void Init(HttpApplication context)
        {
            context.PreSendRequestHeaders += this.OnPreSendRequestHeaders;
        }

        /// <summary>
        /// Disposes of the resources (other than memory) used by this module.
        /// </summary>
        public void Dispose()
        {
        }

        /// <summary>
        /// Event raised just before ASP.NET sends HTTP headers to the client.
        /// </summary>
        /// <param name="sender">Event source.</param>
        /// <param name="e">Event arguments.</param>
        protected void OnPreSendRequestHeaders(object sender, EventArgs e)
        {
            NameValueCollection headers = HttpContext.Current.Response.Headers;
            headers.Remove("Server");
            headers.Remove("ETag");
            headers.Remove("X-Powered-By");
            headers.Remove("X-AspNet-Version");
            headers.Remove("X-AspNetMvc-Version");
        }
    }
}

该模块通过web.config安装,<system.web>适用于IIS 6,安装在<system.webServer>IIS 7下.