NLog 5.0 introduces new fluentLogEventBuilder that can be activated with one of these extensions methods forILogger:

• ForLogEvent - Builds base LogEvent
• ForTraceEvent - Builds LogEvent with Trace-LogLevel
• ForDebugEvent - Builds LogEvent with Debug-LogLevel
• ForInfoEvent - Builds LogEvent with Info-LogLevel
• ForWarnEvent - Builds LogEvent with Warn-LogLevel
• ForErrorEvent - Builds LogEvent with Error-LogLevel
• ForFatalEvent - Builds LogEvent with Fatal-LogLevel
• ForExceptionEvent - Builds LogEvent with Exception and Error-LogLevel

To complete the fluent builder then callLog() to capture availablecallsite information with help fromCaller Member Attributes, and then writes the actual LogEvent to any configured NLog targets.

Replaces the oldFluent-namespace and also reduces memory-allocation when LogLevel not enabled.

_logger.ForInfoEvent().Message("This is a fluent message {0}.","test").Property("PropertyName","PropertyValue").Log();

try{stringtext=File.ReadAllText(path);}catch(Exceptionex){_logger.ForExceptionEvent(ex).Message("Error reading file '{0}'.",path).Property("Test","InfoWrite").Log();}