For the following "project" I am getting a very annoying and inexplicable error when resolving Unity for DI.
InvalidOperationException - The type LogWriter cannot be constructed.
You must configure the container to supply this value.
?ex.Message; "Resolution of the dependency failed, type =
"WindowsFormsApplication1.Performance", name =
"(none)".
Exception occurred while: while resolving.
Exception
is: InvalidOperationException - The type LogWriter cannot be
constructed. You must configure the container to supply this
value.
-----------------------------------------------
At the
time of the exception, the container was:
Resolving
WindowsFormsApplication1.Performance,(none)
Resolving parameter
"lw" of constructor
WindowsFormsApplication1.Performance(Microsoft.Practices.EnterpriseLibrary.Logging.LogWriter
lw,
Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.ExceptionManager
em)
Resolving
Microsoft.Practices.EnterpriseLibrary.Logging.LogWriter,(none)
"
?ex.StackTrace; " at
Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type t, Object
existing, String name, IEnumerable1 resolverOverrides) in
e:\Builds\Unity\UnityTemp\Compile\Unity\Unity\Src\UnityContainer.cs:line
515
at Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type
t, String name, IEnumerable
1 resolverOverrides) in
e:BuildsUnityUnityTempCompileUnityUnitySrcUnityContainer.cs:line
485
at Microsoft.Practices.Unity.UnityContainer.Resolve(Type t,
String name, ResolverOverride[] resolverOverrides) in
e:BuildsUnityUnityTempCompileUnityUnitySrcUnityContainer.cs:line
173
at
Microsoft.Practices.Unity.UnityContainerExtensions.Resolve[T](IUnityContainer
container, ResolverOverride[] overrides) in
e:BuildsUnityUnityTempCompileUnityUnitySrcUnityContainerExtensions.cs:line
504
at WindowsFormsApplication1.Form1.OnLoad(EventArgs e) in
D:DevzoneTaskingWindowsFormsApplication1Form1.cs:line 33"
In a form:
protected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
try
{
IUnityContainer container = new UnityContainer();
Performance p = container.Resolve<Performance>();
}
catch (Exception ex)
{
}
}
Dependency class:
public class Performance
{
public Performance(LogWriter lw, ExceptionManager em)
{
}
}
Configuration File:
<?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" />
<section name="exceptionHandling" type="Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.Configuration.ExceptionHandlingSettings, Microsoft.Practices.EnterpriseLibrary.ExceptionHandling, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="true" />
</configSections>
<loggingConfiguration name="" tracingEnabled="true" defaultCategory="General">
<listeners>
<add name="Event Log Listener" type="Microsoft.Practices.EnterpriseLibrary.Logging.TraceListeners.FormattedEventLogTraceListener, Microsoft.Practices.EnterpriseLibrary.Logging, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
listenerDataType="Microsoft.Practices.EnterpriseLibrary.Logging.Configuration.FormattedEventLogTraceListenerData, Microsoft.Practices.EnterpriseLibrary.Logging, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
source="Enterprise Library Logging" formatter="Text Formatter"
log="" machineName="." traceOutputOptions="None" />
</listeners>
<formatters>
<add type="Microsoft.Practices.EnterpriseLibrary.Logging.Formatters.TextFormatter, Microsoft.Practices.EnterpriseLibrary.Logging, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
template="Timestamp: {timestamp}{newline}
Message: {message}{newline}
Category: {category}{newline}
Priority: {priority}{newline}
EventId: {eventid}{newline}
Severity: {severity}{newline}
Title:{title}{newline}
Machine: {localMachine}{newline}
App Domain: {localAppDomain}{newline}
ProcessId: {localProcessId}{newline}
Process Name: {localProcessName}{newline}
Thread Name: {threadName}{newline}
Win32 ThreadId:{win32ThreadId}{newline}
Extended Properties: {dictionary({key} - {value}{newline})}"
name="Text Formatter" />
</formatters>
<categorySources>
<add switchValue="All" name="General">
<listeners>
<add name="Event Log Listener" />
</listeners>
</add>
<add switchValue="All" name="Category2" />
</categorySources>
<specialSources>
<allEvents switchValue="All" name="All Events" />
<notProcessed switchValue="All" name="Unprocessed Category" />
<errors switchValue="All" name="Logging Errors & Warnings">
<listeners>
<add name="Event Log Listener" />
</listeners>
</errors>
</specialSources>
</loggingConfiguration>
<exceptionHandling>
<exceptionPolicies>
<add name="Policy">
<exceptionTypes>
<add name="All Exceptions" type="System.Exception, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
postHandlingAction="NotifyRethrow" />
</exceptionTypes>
</add>
</exceptionPolicies>
</exceptionHandling>
</configuration>
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