Une erreur d'activation s'est produite lors de la tentative d'obtention de l'instance de type LogWriter, clé ""?

J'ai asp.net site web. J'ai ajouté la référence de Microsoft.Practices.EnterpriseLibrary.Logging.dll sur le site.

dans le web.cofig fichier, j'ai défini comme ci-dessous.

    <?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
<section name="loggingConfiguration" type="Microsoft.Practices.EnterpriseLibrary.Logging.Configuration.LoggingSettings, Microsoft.Practices.EnterpriseLibrary.Logging, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="true" />
</configSections>
<loggingConfiguration name="Logging Application Block" tracingEnabled="true"
defaultCategory="General" logWarningsWhenNoCategoriesMatch="true">
<listeners>
<add name="Rolling Flat File Trace Listener" type="Microsoft.Practices.EnterpriseLibrary.Logging.TraceListeners.RollingFlatFileTraceListener, Microsoft.Practices.EnterpriseLibrary.Logging"
listenerDataType="Microsoft.Practices.EnterpriseLibrary.Logging.Configuration.RollingFlatFileTraceListenerData, Microsoft.Practices.EnterpriseLibrary.Logging"
fileName="C:\Temp\RollingFlatFile.log" footer="----------------------------------------"
formatter="Text Formatter" header="----------------------------------------"
rollFileExistsBehavior="Increment" rollInterval="None" rollSizeKB="20"
timeStampPattern="yyyy-MM-dd" maxArchivedFiles="3" traceOutputOptions="None"
filter="All" />
</listeners>
<formatters>
<add type="Microsoft.Practices.EnterpriseLibrary.Logging.Formatters.TextFormatter, Microsoft.Practices.EnterpriseLibrary.Logging"
template="Timestamp: {timestamp(local)}{tab}Message: {message}{tab}Category: {category}{tab}Priority: {priority}{tab}EventId: {eventid}{tab}ActivityId: {property(ActivityId)}{tab}Severity: {severity}{tab}Title:{title}{tab}"
name="Brief Format Text" />
<add type="Microsoft.Practices.EnterpriseLibrary.Logging.Formatters.TextFormatter, Microsoft.Practices.EnterpriseLibrary.Logging"
template="Timestamp: {timestamp}{tab}Message: {message}{tab}Category: {category}{tab}Priority: {priority}{tab}EventId: {eventid}{tab}Severity: {severity}{tab}Title: {title}{tab}Activity ID: {property(ActivityId)}{tab}Machine: {localMachine}{tab}App Domain: {localAppDomain}{tab}ProcessId: {localProcessId}{tab}Process Name: {localProcessName}{tab}Thread Name: {threadName}{tab}Win32 ThreadId:{win32ThreadId}{tab}Extended Properties: {dictionary({key} - {value}{tab})}"
name="Text Formatter" />
</formatters>
<logFilters>
<add type="Microsoft.Practices.EnterpriseLibrary.Logging.Filters.PriorityFilter, Microsoft.Practices.EnterpriseLibrary.Logging"
minimumPriority="2" maximumPriority="99" name="Priority Filter" />
<add type="Microsoft.Practices.EnterpriseLibrary.Logging.Filters.LogEnabledFilter, Microsoft.Practices.EnterpriseLibrary.Logging"
enabled="true" name="LogEnabled Filter" />
<add type="Microsoft.Practices.EnterpriseLibrary.Logging.Filters.CategoryFilter, Microsoft.Practices.EnterpriseLibrary.Logging"
categoryFilterMode="AllowAllExceptDenied" name="Category Filter">
<categoryFilters>
<add name="BlockedByFilter" />
</categoryFilters>
</add>
</logFilters>
<categorySources>
<add switchValue="All" name="Important">
<listeners>
<add name="Formatted EventLog TraceListener" />
<add name="Rolling Flat File Trace Listener" />
</listeners>
</add>
</categorySources>
<specialSources>
<allEvents switchValue="All" name="All Events" />
<notProcessed switchValue="All" name="Unprocessed Category">
<listeners>
<add name="UnprocessedFlatFile" />
</listeners>
</notProcessed>
<errors switchValue="All" name="Logging Errors &amp; Warnings">
<listeners>
<add name="Formatted EventLog TraceListener" />
</listeners>
</errors>
</specialSources>
</loggingConfiguration>
</configuration>

Quand je lance l'exception de code passe-bas de la place.

defaultWriter = EnterpriseLibraryContainer.Current.GetInstance<LogWriter>();
//Activation error occured while trying to get instance of type LogWriter, key ""

Comment résoudre ce problème?

source d'informationauteur James123