1 publicclassNullLogger:ILogger
 2 {
 3 privatestaticreadonlyILogger _instance =newNullLogger();
 4 publicstaticILoggerInstance
 5 {
 6  get
 7 {
 8 return _instance;
 9 }
10 }
11 #region ILogger 成员
12
13 public bool IsEnabled(LogLevel level)
14 {
15 returnfalse;
16 }
17
18 publicvoidLog(LogLevel level,Exception exception,string format,paramsobject[] args)
19 {
20
21 }
22
23 #endregion
24 }

 1 publicclassLoggingModule:Module
 2 {
 3 privatereadonlyConcurrentDictionary<string,ILogger> _loggerCache;
 4
 5 publicLoggingModule()
 6 {
 7  _loggerCache =newConcurrentDictionary<string,ILogger>();
 8 }
 9
10 protectedoverridevoidLoad(ContainerBuilder moduleBuilder)
11 {
12 // by default, use Orchard's logger that delegates to Castle's logger factory
13  moduleBuilder.RegisterType<CastleLoggerFactory>().As<ILoggerFactory>().InstancePerLifetimeScope();
14  moduleBuilder.RegisterType<OrchardLog4netFactory>().As<Castle.Core.Logging.ILoggerFactory>().InstancePerLifetimeScope().WithParameter(newNamedParameter("isFullTrust",false));
15
16 // call CreateLogger in response to the request for an ILogger implementation
17  moduleBuilder.Register(CreateLogger).As<ILogger>().InstancePerDependency();
18 }
19
20 protectedoverridevoidAttachToComponentRegistration(IComponentRegistry componentRegistry,IComponentRegistration registration)
21 {
22 var implementationType = registration.Activator.LimitType;
23
24 // build an array of actions on this type to assign loggers to member properties
25 var injectors =BuildLoggerInjectors(implementationType).ToArray();
26
27 // if there are no logger properties, there's no reason to hook the activated event
28 if(!injectors.Any())
29 return;
30
31 // otherwise, whan an instance of this component is activated, inject the loggers on the instance
32  registration.Activated+=(s, e)=>
33 {
34 foreach(var injector in injectors)
35  injector(e.Context, e.Instance);
36 };
37 }
38
39 privateIEnumerable<Action<IComponentContext,object>>BuildLoggerInjectors(Type componentType)
40 {
41 // Look for settable properties of type "ILogger"
42 var loggerProperties = componentType
43 .GetProperties(BindingFlags.SetProperty|BindingFlags.Public|BindingFlags.Instance)
44 .Select(p =>new
45 {
46 PropertyInfo= p,
47  p.PropertyType,
48 IndexParameters= p.GetIndexParameters(),
49 Accessors= p.GetAccessors(false)
50 })
51 .Where(x => x.PropertyType==typeof(ILogger))// must be a logger
52 .Where(x => x.IndexParameters.Count()==0)// must not be an indexer
53 .Where(x => x.Accessors.Length!=1|| x.Accessors[0].ReturnType==typeof(void));//must have get/set, or only set
54
55 // Return an array of actions that resolve a logger and assign the property
56 foreach(var entry in loggerProperties)
57 {
58 var propertyInfo = entry.PropertyInfo;
59  yield return(ctx, instance)=>
60 {
61 string component = componentType.ToString();
62 if(component != instance.GetType().ToString())
63 {
64 return;
65 }
66 var logger = _loggerCache.GetOrAdd(component, key => ctx.Resolve<ILogger>(newTypedParameter(typeof(Type), componentType)));
67  propertyInfo.SetValue(instance, logger,null);
68 };
69 }
70 }
71
72 privatestaticILoggerCreateLogger(IComponentContext context,IEnumerable<Parameter> parameters)
73 {
74 // return an ILogger in response to Resolve<ILogger>(componentTypeParameter)
75 var loggerFactory = context.Resolve<ILoggerFactory>();
76 var containingType = parameters.TypedAs<Type>();
77 return loggerFactory.CreateLogger(containingType);
78 }
79 }