DI Unity Container resolution error - dependency-injection

Question

I am trying to fake Enterprise Library LogWriter so it doesn't perform any logging when I run unit tests, so it looks like this in simplified version:
public class MockLogger : ILogger
{
public MockLogger()
{
}
public void Write(object message)
{
}
public void Write(object message, string category)
{
}
public void Write(object message, string category, int eventId)
{
}
public void Write(object message, string category, int eventId, int priority)
{
}
public void Write(object message, string category, int eventId, int priority, TraceEventType severity)
{
}
}
public class Logger : ILogger
{
LogWriter writer;
public Logger()
{
writer = (new LogWriterFactory()).Create();
}
public Logger(LogWriter logWriter)
{
writer = logWriter;
}
public void Write(LogEntry logEntry)
{
writer.Write(logEntry);
}
public void Write(object message)
{
writer.Write(message);
}
public void Write(object message, string category)
{
writer.Write(message, category);
}
public void Write(object message, string category, int eventId)
{
writer.Write(message, category, eventId);
}
public void Write(object message, string category, int eventId, int priority)
{
writer.Write(message, category, eventId, priority);
}
public void Write(object message, string category, int eventId, int priority, TraceEventType severity)
{
writer.Write(message, category, priority, eventId, severity);
}
public bool ShouldLog(LogEntry logEntry)
{
return writer.ShouldLog(logEntry);
}
}
Then i am trying to resolve it thru configuration:
<unity xmlns="http://schemas.microsoft.com/practices/2012/unity">
<alias alias="ILogger" type="ConsoleApplicationTest.ILogger, ConsoleApplicationTest" />
<namespace name="ConsoleApplicationTest" />
<assembly name="ConsoleApplicationTest" />
<container>
<register type="ConsoleApplicationTest.ILogger, ConsoleApplicationTest" name="logger" mapTo="ConsoleApplicationTest.Logger, ConsoleApplicationTest">
</register>
</container>
<container name="Mock">
<register type="ConsoleApplicationTest.ILogger, ConsoleApplicationTest" name="mockLogger" mapTo="ConsoleApplicationTest.MockLogger, ConsoleApplicationTest">
</register>
</container>
var container = new UnityContainer();
container.LoadConfiguration();
var logger = container.Resolve<ILogger>();
The error I am getting is the following:
Resolution of the dependency failed, type =
"ConsoleApplicationTest.ILogger", name = "(none)". Exception occurred
while: while resolving. Exception is: InvalidOperationException - The
type ILogger does not have an accessible constructor.
Both classes have a parameterless constructor. What should I do to resolve this error? Using .NET 4.5

Answer 1

Because you have registered your types with the name="logger" and name="mockLogger" you have created named registrations so you need to pass in the name when calling Resolve:
var container = new UnityContainer();
container.LoadConfiguration();
var logger = container.Resolve<ILogger>("logger"); // or "mockLogger"