Asp.net Mvc中扩展ActionFilterAttribute修改Http Cache Header

在asp.net mvc3中扩展ActionFilterAttribute实现Http Cache Header修改

ActionFilterAttribute 是 System.Web.Mvc.ActionFilterAttribute

来自于：System.Web.Mvc.dll

#region Assembly System.Web.Mvc.dll, v4.0.30319
// C:\Program Files (x86)\Microsoft ASP.NET\ASP.NET MVC 3\Assemblies\System.Web.Mvc.dll
#endregion

using System;

namespace System.Web.Mvc
{
    // Summary:
    //     Represents the base class for filter attributes.
    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, Inherited = true, AllowMultiple = false)]
    public abstract class ActionFilterAttribute : FilterAttribute, IActionFilter, IResultFilter
    {
        // Summary:
        //     Initializes a new instance of the System.Web.Mvc.ActionFilterAttribute class.
        protected ActionFilterAttribute();

        // Summary:
        //     Called by the ASP.NET MVC framework after the action method executes.
        //
        // Parameters:
        //   filterContext:
        //     The filter context.
        public virtual void OnActionExecuted(ActionExecutedContext filterContext);
        //
        // Summary:
        //     Called by the ASP.NET MVC framework before the action method executes.
        //
        // Parameters:
        //   filterContext:
        //     The filter context.
        public virtual void OnActionExecuting(ActionExecutingContext filterContext);
        //
        // Summary:
        //     Called by the ASP.NET MVC framework after the action result executes.
        //
        // Parameters:
        //   filterContext:
        //     The filter context.
        public virtual void OnResultExecuted(ResultExecutedContext filterContext);
        //
        // Summary:
        //     Called by the ASP.NET MVC framework before the action result executes.
        //
        // Parameters:
        //   filterContext:
        //     The filter context.
        public virtual void OnResultExecuting(ResultExecutingContext filterContext);
    }
}

以上是ActionFilterAttribute 类的具体代码，它是抽象类 abstract  ，有四个虚方法 virtual .

User Story：

     作为一个用户, 希望系统可以让我在需要访问系统时能够有快的速度, 以便我能够看到信息，提高我的体验。

为系统添加缓存：

给http header添加缓存值，使用其它缓存系统对web进行缓存，使用合适的缓存策略。

Cache-Control:max-age=value

E-TTL=value

1.扩展ActionFilterAttribute

   CacheHeaderFilter

    using System;
    using System.Web;
    using System.Web.Mvc;

    /// <summary>
    /// The cache filter.
    /// </summary>
    public class CacheHeaderFilter : ActionFilterAttribute
    {
        /// <summary>
        /// ETTL
        /// </summary>
        public int ETTL { get; set; }

        /// <summary>
        /// CacheControlMaxAge
        /// </summary>
        public int CacheControlMaxAge { get; set; }

        /// <summary>
        /// OnActionExecuted
        /// </summary>
        /// <param name="filterContext"></param>
        public override void OnActionExecuted(ActionExecutedContext filterContext)
        {
            var response = filterContext.HttpContext.Response;
            response.Cache.SetCacheability(HttpCacheability.Public);
            response.Cache.SetMaxAge(TimeSpan.FromSeconds(this.CacheControlMaxAge));
            response.Headers.Add("E-TTL", this.ETTL.ToString());
        }

在Asp.net MVC 中使用 CacheHeaderFilter

        /// <summary>
        /// index page
        /// </summary>
        /// <returns></returns>
        [CacheHeaderFilter(CacheControlMaxAge = 3600, ETTL = 3600)]
        public ActionResult Index()
        {
            return View();
        }