/// <summary>
/// 利用指定的缓存策略提供程序创建 HtmlCacheableAttribute 对象。
/// </summary>
/// <param name="policyProviderType">缓存策略提供程序类型</param>
public CacheableAttribute(Type policyProviderType)
{
if (policyProviderType.IsSubclassOf(typeof(IMvcCachePolicyProvider)))
{
CachePolicyProvider = Activator.CreateInstance(policyProviderType).CastTo <IMvcCachePolicyProvider>();
return;
}
else if (policyProviderType.IsSubclassOf(typeof(ICachePolicyProvider)))
{
CachePolicyProvider = new MvcCachePolicyProviderWrapper(Activator.CreateInstance(policyProviderType).CastTo <ICachePolicyProvider>());
return;
}
throw new InvalidOperationException("配置错误，类型必须从 IHtmlCachePolicyProvider 或 IMvcCachePolicyProvider 派生");
}
/// <summary>
/// 获取缓存策略
/// </summary>
/// <param name="context">MVC 请求上下文</param>
/// <returns></returns>
protected override CachePolicy CreateCachePolicy(ControllerContext context, ActionDescriptor action, IDictionary <string, object> parameters)
{
if (CachePolicyProvider != null)
{
return(CachePolicyProvider.CreateCachePolicy(context, action, parameters));
}
var httpMethod = context.HttpContext.Request.HttpMethod;
if (!httpMethod.EqualsIgnoreCase("get") && !httpMethod.EqualsIgnoreCase("header"))//如果不是GET或Header请求，都不予缓存。
{
return(null);
}
var provider = context.Controller as IMvcCachePolicyProvider;
if (provider == null)
{
var _provider = context.Controller as ICachePolicyProvider;
if (_provider != null)
{
provider = new MvcCachePolicyProviderWrapper(_provider);
}
}
var policy = provider.CreateCachePolicy(context, action, parameters);
if (policy != null)
{
return(policy);
}
return(MvcEnvironment.CreateCachePolicy(context, action, parameters));
}