在Enterprise Library for .NET Framework 2.0中使用外部的配置元数据的文件(my.config)

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最新推荐文章于 2025-08-21 23:21:52 发布

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示例代码下载

一般情况下，包含配置元数据的文件为Windows应用程序的App.Config或Web应用程序的Web.Config文件.这里介绍如何使用外部的置元数据的文件.

通常的方法
首先下面的一段代码是通常的做法,在App.config中写入配置信息,程序中用到了两个Block: Data Access Application Block和Exception Application Block.
AppService.vb

Public Class AppService Class AppService

Sub ProcessA()Sub ProcessA()

Try

'生成Database

Dim db As Database = DatabaseFactory.CreateDatabase("rippleyong's ConnectionString")

'产生一个异常

db.ExecuteNonQuery("Get a Exception")

Catch ex As Exception

If ExceptionPolicy.HandleException(ex, "rippleyong's Policy") Then Throw

End Try

End Sub

End Class

App.config

<? xml version="1.0" encoding="utf-8" ?>

< configuration >

< configSections >

< section name ="exceptionHandling" type ="Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.Configuration.ExceptionHandlingSettings, Microsoft.Practices.EnterpriseLibrary.ExceptionHandling, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null" />

< section name ="dataConfiguration" type ="Microsoft.Practices.EnterpriseLibrary.Data.Configuration.DatabaseSettings, Microsoft.Practices.EnterpriseLibrary.Data, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null" />

</ configSections >

< exceptionHandling >

< exceptionPolicies >

< add name ="rippleyong's Policy" >

< exceptionTypes >

< add type ="System.Exception, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"

postHandlingAction ="NotifyRethrow" name ="Exception" >

< exceptionHandlers >

< add exceptionMessage ="Replace ExceptionMessage,Haha !!!" replaceExceptionType ="System.Exception, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"

type ="Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.ReplaceHandler, Microsoft.Practices.EnterpriseLibrary.ExceptionHandling, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null"

name ="Replace Handler" />

</ exceptionHandlers >

</ add >

</ exceptionTypes >

</ add >

</ exceptionPolicies >

</ exceptionHandling >

< connectionStrings >

< add name ="rippleyong's ConnectionString" connectionString ="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|ripple.mdf;User Instance=true;"

providerName ="System.Data.SqlClient" />

</ connectionStrings >

</ configuration >

调用外部的配置元数据文件(结合程序配置文件)
如何使用外部的扩展配置元数据文件呢,这里需要通过配置工具(Enterprise Library Configuration)添加一个Configuration Sources 节点在App.config(web.config)中.添加一个选择File Configuration Source,在File中选择外部的配置元数据文件(在这里是ExternalApp.config)
Configuration Source结构图

Enterprise Library Configuration

App.config

<? xml version="1.0" encoding="utf-8" ?>

< configuration >

< configSections >

< section name ="enterpriseLibrary.ConfigurationSource" type ="Microsoft.Practices.EnterpriseLibrary.Common.Configuration.ConfigurationSourceSection, Microsoft.Practices.EnterpriseLibrary.Common, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null" />

</ configSections >

< enterpriseLibrary .ConfigurationSource selectedSource ="System Configuration Source" >

< sources >

< add name ="File Configuration Source" type ="Microsoft.Practices.EnterpriseLibrary.Common.Configuration.FileConfigurationSource, Microsoft.Practices.EnterpriseLibrary.Common, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null"

filePath ="C:\Documents and Settings\Administrator\My Documents\Visual Studio 2005\EnterpriseLibraryTest\EnterpriseLibraryTest\ExternalConfiguration\ExternalApp.config" />

< add name ="System Configuration Source" type ="Microsoft.Practices.EnterpriseLibrary.Common.Configuration.SystemConfigurationSource, Microsoft.Practices.EnterpriseLibrary.Common, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null" />

</ sources >

</ enterpriseLibrary.ConfigurationSource >

</ configuration >

ExternalApp.config

< configuration >

< configSections >

</ configSections >

< exceptionHandling >

< exceptionPolicies >

< add name ="rippleyong's Policy" >

< exceptionTypes >

< add type ="System.Exception, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"

postHandlingAction ="NotifyRethrow" name ="Exception" >

< exceptionHandlers >

< add exceptionMessage ="Rplace ExceptionMessage HaHa." replaceExceptionType ="System.ApplicationException, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"

type ="Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.ReplaceHandler, Microsoft.Practices.EnterpriseLibrary.ExceptionHandling, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null"

name ="Replace Handler" />

</ exceptionHandlers >

</ add >

</ exceptionTypes >

</ add >

</ exceptionPolicies >

</ exceptionHandling >

< connectionStrings >

< add name ="rippleyong's connetionString" connectionString ="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|ripple.mdf;User Instance=true;"

providerName ="System.Data.SqlClient" />

</ connectionStrings >

</ configuration >

使用单独的ConfigurationSources
从上面的例子中我们可以看到,还是不是完全独立的,因为你必须在App.Config(Web.Config)中告诉Enterprise Library外部配置元数据文件的位置.
下面的代码演示了直接在程序中找到外部配置元数据文件.

Sub ProcessB() Sub ProcessB()

Try

Dim dataSource As New FileConfigurationSource("data-filesource.config")

Dim dbFactory As DatabaseProviderFactory = New DatabaseProviderFactory(dataSource)

Dim db As Database = dbFactory.Create("rippleyong's ConnectionString")

db.ExecuteNonQuery("Get a Exception")

Catch ex As Exception

Dim dataSource As New FileConfigurationSource("exceprion-filesource.config")

Dim exceptionFactory As ExceptionPolicyFactory = New ExceptionPolicyFactory(dataSource)

Dim exceptionPolicy As ExceptionPolicyImpl = exceptionFactory.Create("rippleyong's Policy")

If exceptionPolicy.HandleException(ex) Then Throw

End Try

End Sub

data-filesource.config

<? xml version="1.0" encoding="utf-8" ?>

< configuration >

< configSections >

</ configSections >

< connectionStrings >

< add name ="rippleyng's Connection" connectionString ="Database=ripple;Server=(local)\SQLEXPRESS;Integrated Security=SSPI;"

providerName ="System.Data.SqlClient" />

</ connectionStrings >

</ configuration >

exception-filesource.config

<? xml version="1.0" encoding="utf-8" ?>

< configuration >

< configSections >

</ configSections >

< exceptionHandling >

< exceptionPolicies >

< add name ="rippleyong's Policy" >

< exceptionTypes >

< add type ="System.Exception, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"

postHandlingAction ="ThrowNewException" name ="Exception" >

< exceptionHandlers >

< add exceptionMessage ="Rplace ExceptionMessage HaHa." replaceExceptionType ="System.ApplicationException, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"

type ="Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.ReplaceHandler, Microsoft.Practices.EnterpriseLibrary.ExceptionHandling, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null"

name ="Replace Handler" />

</ exceptionHandlers >

</ add >

</ exceptionTypes >

</ add >

</ exceptionPolicies >

</ exceptionHandling >

</ configuration >