clean stc ane adding clas 是什麽 idc 內部函數 ash

這篇就三種攔截模式進行一下探索。

特性總結

	類型	特點	其它
InterfaceInterceptor	Innstance	僅單接口	類內部函數互相引用無法引起攔截行為
TransparentProxyInterceptor	Instance	多接口(接口之間能夠切換) MarshalByRef 執行緩慢 接口類型（virtual, non-virtual, or interface）	類內部函數互相引用能夠引起攔截行為
VirtualMethodInterceptor	Type	多接口 不能用在已有對象上，接口函數必須為virtual	類內部函數互相引用也能引起攔截行為

回顧一下類的聲明。兩個接口，一個實現。

fsharp實現接口函數的方法與csharp並不全然一致，會造成一些實現上的困擾，這在後面會提到。

type ITenantStore = 
    abstract member Msg : unit->unit


type TenantStore() as x= 
    //do printfn "new TenantStore %A" (x.GetHashCode())
    interface ITenantStore with
        member this.Msg() = printfn "Hello, it‘s TenantStore"
    interface IDisposable with
        member this.Dispose() = printfn "TenantStore hase been cleaned"

以下進行一些測試。

let showregistrations (container:UnityContainer) = 
    container.Registrations |> Seq.iter (fun i -> printfn "Regist Type:%A" i.RegisteredType)


using(new UnityContainer())(fun ctner->
    ctner.AddNewExtension<Interception>() |> ignore
    ctner.RegisterType<ITenantStore, TenantStore>(new Interceptor<TransparentProxyInterceptor>(),//興許對此註入策略進行切換
                                                  new InterceptionBehavior<LogingInterceptionBehavior>()) |> ignore
    showregistrations ctner
    let t = ctner.Resolve<ITenantStore>()
    t.Msg())

showregistrations 顯示已註冊的類型。用來展示註冊內部的信息。另外，在交互式代碼中使用using相較於use更為的合適，FSI聲明的對象的生命周期是全局的，在做試驗的時候無法控制container。重復清環境不太方便。

TransparentProxyInterceptor的結果

Regist Type:Microsoft.Practices.Unity.IUnityContainer
Regist Type:Microsoft.Practices.Unity.InterceptionExtension.InjectionPolicy
Regist Type:FSI_0002+ITenantStore
From the logging interceptor: "Invoke method System.Type GetType():System.Object at 16:20:45"
From the logging interceptor: "Method System.Type GetType():System.Object returned FSI_0002+TenantStore at 16:20:45"
From the logging interceptor: "Invoke method Void Msg():FSI_0002+ITenantStore at 16:20:45"
Hello, it‘s TenantStore
From the logging interceptor: "Method Void Msg():FSI_0002+ITenantStore returned  at 16:20:45"
val it : unit = ()

InterfaceInterceptor的結果

Regist Type:Microsoft.Practices.Unity.IUnityContainer
Regist Type:Microsoft.Practices.Unity.InterceptionExtension.InjectionPolicy
Regist Type:FSI_0002+ITenantStore
From the logging interceptor: "Invoke method Void Msg():FSI_0002+ITenantStore at 16:22:54"
Hello, it‘s TenantStore
From the logging interceptor: "Method Void Msg():FSI_0002+ITenantStore returned  at 16:22:54"
val it : unit = ()

盡管對象有兩個接口，IDiposable接口和ITenantStore接口。攔截仍然成功了，所以支持多對象指的是接口之間的切換，並不是不支持實現多對象的類。

VirtualMethodInterceptor的結果

Regist Type:Microsoft.Practices.Unity.IUnityContainer
Regist Type:Microsoft.Practices.Unity.InterceptionExtension.InjectionPolicy
Regist Type:FSI_0002+ITenantStore
Hello, it‘s TenantStore
val it : unit = ()

攔截失敗。 研究後發覺是由於Fsharp中並不直接支持Virtual方法，Fsharp實現接口成員，默覺得顯示（explicit）實現，想要申明Virtual方法須要一些技巧。
可參考http://cs.hubfs.net/topic/None/73936


再定義一個測試類來試試VirtualMethodInterceptor。

type testClass() = 
    abstract member Test : unit -> unit
    default x.Test() = 
        printfn "hello "

using(new UnityContainer())(fun ctner->
    ctner.AddNewExtension<Interception>() |> ignore
    ctner.RegisterType<testClass>(new Interceptor<VirtualMethodInterceptor>(),
                                  new InterceptionBehavior<LogingInterceptionBehavior>()) |> ignore
    showregistrations ctner
    let t = ctner.Resolve<testClass>()
    t.Test()
    )

結果

Regist Type:Microsoft.Practices.Unity.IUnityContainer
Regist Type:Microsoft.Practices.Unity.InterceptionExtension.InjectionPolicy
Regist Type:FSI_0002+testClass
From the logging interceptor: "Invoke method Void Test():FSI_0002+testClass at 9:30:27"
hello 
From the logging interceptor: "Method Void Test():FSI_0002+testClass returned  at 9:30:27"
val it : unit = ()

攔截成功。

以下稍加改寫原來的類定義。使接口都以virtural的形式暴露出來

type TenantStore() as x= 
    //do printfn "new TenantStore %A" (x.GetHashCode())
    abstract Msg : unit -> unit
    default x.Msg() = 
        printfn "Hello, it‘s TenantStore"
    abstract Dispose : unit -> unit
    default x.Dispose() = 
        printfn "TenantStore hase been cleaned"
    interface ITenantStore with
        member x.Msg() = x.Msg()
    interface IDisposable with
        member x.Dispose() = x.Dispose()

有些繁瑣，接口實現的代碼能夠復用，不幸中的萬幸。

以下的樣例中我同一時候測試一下多接口之間轉換的情況，看看VirtualMethodInterceptor是否也支持多接口。文檔上沒有明白表明。

測試代碼

using(new UnityContainer())(fun ctner->
    ctner.AddNewExtension<Interception>() |> ignore
    ctner.RegisterType<ITenantStore, TenantStore>(new Interceptor<VirtualMethodInterceptor>(),
                                                  new InterceptionBehavior<LogingInterceptionBehavior>()) |> ignore
    ctner.RegisterType<testClass>(new Interceptor<VirtualMethodInterceptor>(),
                                  new InterceptionBehavior<LogingInterceptionBehavior>()) |> ignore
    showregistrations ctner
    let t = ctner.Resolve<ITenantStore>()
    t.Msg()
    let o = (box t) :?
> IDisposable
    o.Dispose()
    )

TransparentProxyInterceptor
成功 結果

Regist Type:Microsoft.Practices.Unity.IUnityContainer
Regist Type:Microsoft.Practices.Unity.InterceptionExtension.InjectionPolicy
Regist Type:FSI_0002+ITenantStore
From the logging interceptor: "Invoke method System.Type GetType():System.Object at 9:38:47"
From the logging interceptor: "Method System.Type GetType():System.Object returned FSI_0010+TenantStore at 9:38:47"
From the logging interceptor: "Invoke method Void Msg():FSI_0002+ITenantStore at 9:38:47"
Hello, it‘s TenantStore
From the logging interceptor: "Method Void Msg():FSI_0002+ITenantStore returned  at 9:38:47"
From the logging interceptor: "Invoke method System.Type GetType():System.Object at 9:38:47"
From the logging interceptor: "Method System.Type GetType():System.Object returned FSI_0010+TenantStore at 9:38:47"
From the logging interceptor: "Invoke method Void Dispose():System.IDisposable at 9:38:47"
TenantStore hase been cleaned
From the logging interceptor: "Method Void Dispose():System.IDisposable returned  at 9:38:47"
val it : unit = ()

InterfaceInterceptor
失敗 結果：

Regist Type:Microsoft.Practices.Unity.IUnityContainer
Regist Type:Microsoft.Practices.Unity.InterceptionExtension.InjectionPolicy
Regist Type:FSI_0002+ITenantStore
From the logging interceptor: "Invoke method Void Msg():FSI_0002+ITenantStore at 9:39:44"
Hello, it‘s TenantStore
From the logging interceptor: "Method Void Msg():FSI_0002+ITenantStore returned  at 9:39:44"
System.InvalidCastException: 無法將類型為“DynamicModule.ns.Wrapped_ITenantStore_67632c824c8e42bbad5925d203ac819b”的對象強制轉換為類型“System.IDisposable”。
   在 [email protected](UnityContainer ctner) 位置 E:\WorkHell\fsharp-practise\EnterpriseLibraryUnity\Program.fs:行號 157
   在 Microsoft.FSharp.Core.Operators.Using[T,TResult](T resource, FSharpFunc`2 action)
   在 <StartupCode$FSI_0015>.$FSI_0015.main@()
已因出錯而停止

VirtualMethodInterceptor
成功 結果

Regist Type:Microsoft.Practices.Unity.IUnityContainer
Regist Type:Microsoft.Practices.Unity.InterceptionExtension.InjectionPolicy
Regist Type:FSI_0002+ITenantStore
Regist Type:FSI_0002+testClass
From the logging interceptor: "Invoke method Void Msg():FSI_0017+TenantStore at 9:42:01"
Hello, it‘s TenantStore
From the logging interceptor: "Method Void Msg():FSI_0017+TenantStore returned  at 9:42:01"
From the logging interceptor: "Invoke method Void Dispose():FSI_0017+TenantStore at 9:42:01"
TenantStore hase been cleaned
From the logging interceptor: "Method Void Dispose():FSI_0017+TenantStore returned  at 9:42:01"
val it : unit = ()

通過結果能夠看到TransparentProxyInterceptor在構建的過程中多了一些步驟。翻了一下幫助文檔。說這個代理是使用 TransparentProxy/RealProxy infrastructure生成的。因而速度最慢。

而另兩個則是通過動態代碼生成的（這是什麽？反射？）。


這裏能夠有個小的結論了，InterfaceInterceptor最小巧有用，其它兩個或多或少在使用上都要留意一下各自的特性。
再看看可替換性。

(box t) :?> TenantStore

結果
TransparentInterceptor 失敗
VirtualMethodInterceptor 成功
InterfaceInterceptor 失敗 和料想的一致

以上

通過fsharp 使用Enterprise Library Unity 3 - 三種攔截模式的探索