How to delay static initialization within a property
- by Mystagogue
I've made a class that is a cross between a singleton (fifth version) and a (dependency injectable) factory. Call this a "Mono-Factory?" It works, and looks like this:
public static class Context
{
public static BaseLogger LogObject = null;
public static BaseLogger Log
{
get
{
return LogFactory.instance;
}
}
class LogFactory
{
static LogFactory() { }
internal static readonly BaseLogger instance = LogObject ?? new BaseLogger(null, null, null);
}
}
//USAGE EXAMPLE:
//Optional initialization, done once when the application launches...
Context.LogObject = new ConLogger();
//Example invocation used throughout the rest of code...
Context.Log.Write("hello", LogSeverity.Information);
The idea is for the mono-factory could be expanded to handle more than one item (e.g. more than a logger). But I would have liked to have made the mono-factory look like this:
public static class Context
{
private static BaseLogger LogObject = null;
public static BaseLogger Log
{
get
{
return LogFactory.instance;
}
set
{
LogObject = value;
}
}
class LogFactory
{
static LogFactory() { }
internal static readonly BaseLogger instance = LogObject ?? new BaseLogger(null, null, null);
}
}
The above does not work, because the moment the Log property is touched (by a setter invocation) it causes the code path related to the getter to be executed...which means the internal LogFactory "instance" data is always set to the BaseLogger (setting the "LogObject" is always too late!).
So is there a decoration or other trick I can use that would cause the "get" path of the Log property to be lazy while the set path is being invoked?
