如何为PostSharp属性添加参数？

Question

我有一个简单的PostSharp日志记录属性:

[Serializable]
public class MethodLoggingAttribute : OnMethodBoundaryAspect
{
    private ILog _logger;
    public override void OnEntry(MethodExecutionEventArgs eventArgs)
    {
        _logger = LogManager.GetLogger(eventArgs.Method.DeclaringType.ToString());
        _logger.DebugFormat("Entered {0}", eventArgs.Method.Name);
    }
}

我想通过向日志条目添加有关方法参数的信息来使此属性更加灵活,但仅在需要时才这样做.

[Serializable]
public class MethodLoggingAttribute : OnMethodBoundaryAspect
{
    private ILog _logger;
    public override void OnEntry(MethodExecutionEventArgs eventArgs)
    {
        _logger = LogManager.GetLogger(eventArgs.Method.DeclaringType.ToString());

        // if ShowParameters = true
        _logger.DebugFormat("Entered {0} with args:{1}", eventArgs.Method.Name, args);
        // else
        _logger.DebugFormat("Entered {0}", eventArgs.Method.Name);
        // endif
    }
}

带有IF的伪代码是我不知道该怎么做的.如何将其传递给属性？我希望它看起来像这样,但我不知道如何在属性代码中处理它:

[MethodLogging(ShowParameters=true)]
public void SomeCrazyMethod(int CustomerId, string SecretName) {...}

Answer 1

只需声明一个属性

[Serializable]
public class MethodLoggingAttribute : OnMethodBoundaryAspect
{
    private ILog _logger;
    public override void OnEntry(MethodExecutionEventArgs eventArgs)
    {
        _logger = LogManager.GetLogger(eventArgs.Method.DeclaringType.ToString());
        if(ShowParameters = true)
        {
            _logger.DebugFormat("Entered {0} with args:{1}", eventArgs.Method.Name, args);
        }
        else
        {
            _logger.DebugFormat("Entered {0}", eventArgs.Method.Name);
        }
    }

    private bool m_ShowParameters;

    public bool ShowParameters
    {
        get { return m_ShowParameters; }
        set { m_ShowParameters = value; }
    }
}

然后你可以用你提到的方式指定它.