[Asp.net mvc]OutputCacheAttribute

时间:2024-01-08 23:07:26

什么是Cache?

缓存在web应用中是一种以空间换去时间的技术,把频繁访问并且不经常变化的数据存储到内存中,以达到快速访问的目的。在web应用中是比较常见的优化方式。

OutputCacheAttribute

表示一个特性,该特性用于标记将缓存其输出的操作方法。

OutpuCacheAttribute定义

代码片段

[AttributeUsageAttribute(AttributeTargets.Class|AttributeTargets.Method, Inherited = true,
AllowMultiple = false)]
public class OutputCacheAttribute : ActionFilterAttribute,
IExceptionFilter

从上面的代码中可以看到该特性可以应用在类,方法上面。在mvc中,就可以直接在控制器上面或者控制器中的Action上面直接使用,做到细粒度的对缓存的控制。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc; namespace Wolfy.OutputCacheDemo.Controllers
{
[OutputCache(Duration = )]
public class HomeController : Controller
{
// GET: Home
public string Index()
{
return DateTime.Now.ToString();
}
}
}

上面的代码是将OutputCache特性标记在了控制器类上,以达到该控制器上所有的Action都将应用该特性,过期时间设置为10s。10s后缓存过期,再访问就会更新时间。

[Asp.net mvc]OutputCacheAttribute

OutputCache特性也可以设置在Action方法上面,以达到更细粒度的控制缓存。

代码片段

    public class HomeController : Controller
{
[OutputCache(Duration = )]
// GET: Home
public string Index()
{
return DateTime.Now.ToString();
}
}

此时,只有Index的页面进行了缓存。

[Asp.net mvc]OutputCacheAttribute

WebConfig

如果多个控制器或者Action使用相同的缓存配置,可以在配置文件中进行统一配置。

  <system.web>
<caching>
<outputCacheSettings>
<outputCacheProfiles >
<add name='myoutputcache' duration='10'/>
</outputCacheProfiles>
</outputCacheSettings>
</caching>
<compilation debug="true" targetFramework="4.5"/>
<httpRuntime targetFramework="4.5"/>
</system.web>

应用名称为myoutputcache的缓存

    public class HomeController : Controller
{
[OutputCache(CacheProfile = "myoutputcache")]
// GET: Home
public string Index()
{
return DateTime.Now.ToString();
}
}

Note:

当控制器和Action同时使用了OutputCache特性时,以Action为主。

OutputCache参数

#region Assembly System.Web.Mvc.dll, v5.2.2.0
#endregion using System;
using System.Web.UI; namespace System.Web.Mvc
{
// Summary:
// Represents an attribute that is used to mark an action method whose output
// will be cached.
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, Inherited = true, AllowMultiple = false)]
public class OutputCacheAttribute : ActionFilterAttribute, IExceptionFilter
{
// Summary:
// Initializes a new instance of the System.Web.Mvc.OutputCacheAttribute class.
public OutputCacheAttribute(); // Summary:
// Gets or sets the cache profile name.
//
// Returns:
// The cache profile name.
public string CacheProfile { get; set; }
//
// Summary:
// Gets or sets the child action cache.
//
// Returns:
// The child action cache.
public static System.Runtime.Caching.ObjectCache ChildActionCache { get; set; }
//
// Summary:
// Gets or sets the cache duration, in seconds.
//
// Returns:
// The cache duration.
public int Duration { get; set; }
//
// Summary:
// Gets or sets the location.
//
// Returns:
// The location.
public OutputCacheLocation Location { get; set; }
//
// Summary:
// Gets or sets a value that indicates whether to store the cache.
//
// Returns:
// true if the cache should be stored; otherwise, false.
public bool NoStore { get; set; }
//
// Summary:
// Gets or sets the SQL dependency.
//
// Returns:
// The SQL dependency.
public string SqlDependency { get; set; }
//
// Summary:
// Gets or sets the vary-by-content encoding.
//
// Returns:
// The vary-by-content encoding.
public string VaryByContentEncoding { get; set; }
//
// Summary:
// Gets or sets the vary-by-custom value.
//
// Returns:
// The vary-by-custom value.
public string VaryByCustom { get; set; }
//
// Summary:
// Gets or sets the vary-by-header value.
//
// Returns:
// The vary-by-header value.
public string VaryByHeader { get; set; }
//
// Summary:
// Gets or sets the vary-by-param value.
//
// Returns:
// The vary-by-param value.
public string VaryByParam { get; set; } // Summary:
// Returns a value that indicates whether a child action cache is active.
//
// Parameters:
// controllerContext:
// The controller context.
//
// Returns:
// true if the child action cache is active; otherwise, false.
public static bool IsChildActionCacheActive(ControllerContext controllerContext);
//
// Summary:
// This method is an implementation of System.Web.Mvc.IActionFilter.OnActionExecuted(System.Web.Mvc.ActionExecutedContext)
// and supports the ASP.NET MVC infrastructure. It is not intended to be used
// directly from your code.
//
// Parameters:
// filterContext:
// The filter context.
public override void OnActionExecuted(ActionExecutedContext filterContext);
//
// Summary:
// This method is an implementation of System.Web.Mvc.IActionFilter.OnActionExecuting(System.Web.Mvc.ActionExecutingContext)
// and supports the ASP.NET MVC infrastructure. It is not intended to be used
// directly from your code.
//
// Parameters:
// filterContext:
// The filter context.
public override void OnActionExecuting(ActionExecutingContext filterContext);
//
// Summary:
// This method is an implementation of System.Web.Mvc.IExceptionFilter.OnException(System.Web.Mvc.ExceptionContext)
// and supports the ASP.NET MVC infrastructure. It is not intended to be used
// directly from your code.
//
// Parameters:
// filterContext:
// The filter context.
public void OnException(ExceptionContext filterContext);
//
// Summary:
// This method is an implementation of System.Web.Mvc.IResultFilter.OnResultExecuted(System.Web.Mvc.ResultExecutedContext)
// and supports the ASP.NET MVC infrastructure. It is not intended to be used
// directly from your code.
//
// Parameters:
// filterContext:
// The filter context.
public override void OnResultExecuted(ResultExecutedContext filterContext);
//
// Summary:
// Called before the action result executes.
//
// Parameters:
// filterContext:
// The filter context, which encapsulates information for using System.Web.Mvc.AuthorizeAttribute.
//
// Exceptions:
// System.ArgumentNullException:
// The filterContext parameter is null.
public override void OnResultExecuting(ResultExecutingContext filterContext);
}
}

常用的属性

CacheProfile:缓存使用的配置文件的缓存名称。

Duration:缓存时间,以秒为单位,这个除非你的Location=None,可以不添加此属性,其余时候都是必须的。

OutputCacheLocation:枚举类型,缓存的位置。当设置成None时,所有缓存将失效,默认为Any。

namespace System.Web.UI
{
// Summary:
// Specifies the valid values for controlling the location of the output-cached
// HTTP response for a resource.
public enum OutputCacheLocation
{
// Summary:
// The output cache can be located on the browser client (where the request
// originated), on a proxy server (or any other server) participating in the
// request, or on the server where the request was processed. This value corresponds
// to the System.Web.HttpCacheability.Public enumeration value.
Any = ,
//
// Summary:
// The output cache is located on the browser client where the request originated.
// This value corresponds to the System.Web.HttpCacheability.Private enumeration
// value.
Client = ,
//
// Summary:
// The output cache can be stored in any HTTP 1.1 cache-capable devices other
// than the origin server. This includes proxy servers and the client that made
// the request.
Downstream = ,
//
// Summary:
// The output cache is located on the Web server where the request was processed.
// This value corresponds to the System.Web.HttpCacheability.Server enumeration
// value.
Server = ,
//
// Summary:
// The output cache is disabled for the requested page. This value corresponds
// to the System.Web.HttpCacheability.NoCache enumeration value.
None = ,
//
// Summary:
// The output cache can be stored only at the origin server or at the requesting
// client. Proxy servers are not allowed to cache the response. This value corresponds
// to the combination of the System.Web.HttpCacheability.Private and System.Web.HttpCacheability.Server
// enumeration values.
ServerAndClient = ,
}
}

VaryByParam:用于多个输出缓存的字符串列表,并以分号进行分隔。默认时,该字符串与GET方法传递的参数或与POST方法传递的变量相对应。当被设置为多个参数时,输出缓存将会为每个参数都准备一个与之相对应的文档版本。可能值包括none,*,以及任何有效的查询串或POST参数名称。

结语

由于没找到缓存依赖mysql的办法,关于OutputCache的内容就先到这里。

关于缓存依赖的内容,可参考这篇文章

http://www.cnblogs.com/iamlilinfeng/p/4419362.html