无法使用反射访问运行时缓存

为了使您的代码正常工作，您将需要省略绑定标志，现在，处理您的请求的内部.NET代码将了解我们正在尝试查找静态方法: HttpRuntime.Cache.GetType().GetMethod("Get").注意:如果要具有绑定标志(可读性，可理解性)，则可以添加: BindingFlags.Public |BindingFlags.Static ，它与您省略标志时的作用完全相同.如果要执行该方法并获取结果(获取实际的 Cache )，则可以调用刚从 GetMethod收到的 MethodDefinition .使用 Invoke(null，null).I am trying to get the expiry date of a HttpRuntime.Cache object, as per this answer:https://stackoverflow.com/a/350374/1778169The method is: private DateTime GetCacheUtcExpiryDateTime(string cacheKey){ object cacheEntry = Cache.GetType().GetMethod("Get", BindingFlags.Instance | BindingFlags.NonPublic).Invoke(Cache, new object[] { cacheKey, 1 }); PropertyInfo utcExpiresProperty = cacheEntry.GetType().GetProperty("UtcExpires", BindingFlags.NonPublic | BindingFlags.Instance); DateTime utcExpiresValue = (DateTime)utcExpiresProperty.GetValue(cacheEntry, null); return utcExpiresValue;}When I try to use the above method, the first line won't compile:If I replace Cache.GetType() with HttpRuntime.Cache.GetType() it compiles, but I get null returned from this part:cacheType.GetMethod("Get", BindingFlags.Instance | BindingFlags.NonPublic).What am I doing wrong?I am using .NET 4.5. System.Web.Caching is version 4.0.0.0. 解决方案 You should have looked up the original source using the website Microsoft setup in order to find out more details of the HttpRuntime class, specifically the Cache property. If you look at line 2794 of the System.Web.HttpRuntime class you can see the following definition of the Cache property: public static Cache Cache { get { ... } }Now since the property is static you cannot use the binding flags you are using, since right now you are looking for a NonPublic member that belongs to an Instance. In .NET static variables don't belong to an instance, therefor the code you posted will result in an exception being thrown; it simply cannot find the member you are looking for, since it not exists on the instance you provided -- it does however exists on the type definition of the class you are looking into (HttpRuntime).In order to make your code work you will need to omit the binding flags, the internal .NET code that handles your request will now understand we are trying to lookup a static method: HttpRuntime.Cache.GetType().GetMethod("Get"). Note: if you want to have bindingflags (readability, understandabilty), you could add: BindingFlags.Public | BindingFlags.Static, which exactly does the same as whenever you omit the flags.If you want to execute the method and get the result (get the actual Cache) you can invoke the MethodDefinition you just received from the GetMethod using Invoke(null, null). 这篇关于无法使用反射访问运行时缓存的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！ 上岸，阿里云！