我有一个ASP.NET MVC应用程序.我需要缓存一些页面,但只对非验证用户.
我试图使用VaryByCustom =“user”与以下GetVaryByCustomString实现：
public override string GetVaryByCustomString(HttpContext context,string custom)
{
if (custom == "user")
{
if (context.User.Identity.IsAuthenticated)
{
return context.User.Identity.Name;
}
else
{
return "";
}
}
return base.GetVaryByCustomString(context,custom);
}
然而,这并不是我所需要的,因为网页仍然被缓存.只有不同的是,现在是为每个用户单独缓存.
一个可能的解决方案是每当用户被认证时返回Guid.NewGuid(),但是对我来说看起来像是浪费大量资源.
那么你有什么技巧给我吗？
解决方法
所以这里是我做的：
public class NonAuthenticatedOnlyCacheAttribute : OutputCacheAttribute
{
public override void OnResultExecuting(ResultExecutingContext filterContext)
{
var httpContext = filterContext.HttpContext;
if (httpContext.User.Identity.IsAuthenticated)
{
// it's crucial not to cache Authenticated content
Location = OutputCacheLocation.None;
}
// this smells a little but it works
httpContext.Response.Cache.AddValidationCallback(IgnoreAuthenticated,null);
base.OnResultExecuting(filterContext);
}
// This method is called each time when cached page is going to be
// served and ensures that cache is ignored for authenticated users.
private void IgnoreAuthenticated(HttpContext context,object data,ref HttpValidationStatus validationStatus)
{
if (context.User.Identity.IsAuthenticated)
validationStatus = HttpValidationStatus.IgnoreThisRequest;
else
validationStatus = HttpValidationStatus.Valid;
}
}
非常感谢Craig Stuntz谁指出我正确的方向,他的回答我不知不觉中被低估了.
