Class LogValues

Helper methods for logging special variables.

Inheritance

System.Object

LogValues

Namespace: LaunchDarkly.Logging

Assembly: LaunchDarkly.Logging.dll

Syntax

public static class LogValues : Object

Methods

Defer(Func<String>)

Converts any function that returns a string into an object for calling it lazily.

Declaration

public static object Defer(Func<string> stringProvider)

Parameters

Type	Name	Description
System.Func<System.String>	stringProvider	a function that returns a string

Returns

Type	Description
System.Object	an object that calls that function if ToString() is called

Remarks

Sometimes log messages may include a computed value that has enough computational overhead that you would prefer not to compute it unless it really will be logged. The Logger methods that take parameters of type object do not call ToString() to convert those parameters to strings immediately; if logging of this message has been disabled by a Level(ILogAdapter, LogLevel) filter, or some other filtering mechanism defined by the log adapter, or if all logging is disabled because the destination is None, then ToString() is not called. The object returned by Defer simply delegates its ToString() method to the function you provide.

Examples

// Here, ComputeJSONData is only called if debug-level logging is enabled logger.Debug("The JSON data is: {0}", () => ComputeJSONData());

ExceptionSummary(Exception)

Returns an object that lazily constructs a basic exception description.

Declaration

public static object ExceptionSummary(Exception e)

Parameters

Type	Name	Description
System.Exception	e	an exception

Returns

Type	Description
System.Object	an object whose ToString() method provides a description

Remarks

Calling ToString() on the object returned by this method returns a string that includes the name of the exception class, its Message (if any), and the same properties for its InnerException (if any). This string is not constructed unless ToString() is called, so writing exceptions to the log in this way incurs very little overhead if logging is not enabled for the specified log level.

Examples

try { ... } catch (Exception e) { logger.Debug("Caught: {0} {1}", LogValues.ExceptionSummary(e), LogValues.ExceptionTrace(e)); }

ExceptionTrace(Exception)

Returns an object that lazily constructs an exception stacktrace.

Declaration

public static object ExceptionTrace(Exception e)

Parameters

Type	Name	Description
System.Exception	e	an exception

Returns

Type	Description
System.Object	an object whose ToString() method provides a stacktrace

Remarks

Calling ToString() on the object returned by this method returns the exception's stacktrace as a string. This string is not constructed unless ToString() is called, so writing exceptions to the log in this way incurs very little overhead if logging is not enabled for the specified log level.

Examples

try { ... } catch (Exception e) { logger.Debug("Caught: {0} {1}", LogValues.ExceptionSummary(e), LogValues.ExceptionTrace(e)); }