问题
How to replace this code:
string name = "John";
logger.Information("length of name '{name}' is {nameLength}", name, name.Length);
with C# String interpolation like this or similar
string name = "John";
// :-( lost benefit of structured logging: property names not passed to logger
logger.Information($"length of name '{name}' is {name.Length}");
but keep the property names for structured logging to work?
Benefits would be:
- Increased readability
- You'll never forget an argument in arguments list or a property name in message template, especially when you make changes to your logging code
- You always know what this property name will print to your log
回答1:
Add this file to your project. It has ILogger extension methods VerboseInterpolated(), DebugInterpolated() and so on. There are also unit tests here.
Usage with format string
string name = "John";
// add 'Interpolated' to method name: InformationInterpolated() instead of Information()
// add name of the property after the expression. Name is passed to the logger
logger.InformationInterpolated($"length of name '{name:name}' is {name.Length:Length}");
But be careful: it's all too easy to use the wrong method. If you accidentally use the Serilog's method, for example logger.Debug($"length = {length:propertyNameForLogger}"), it will log length = propertyNameForLogger, so no argument value will be logged. This is due to propertyNameForLogger is format for your value.
Usage with anonymous types
string name = "John";
// add 'Interpolated' to method name: InformationInterpolated() instead of Information()
// create an anonymous object with 'new { propertyName }'.
// It's much slower because of using Reflection, but allows to write the variable name only once.
logger.InformationInterpolated($"length of name '{new { name }}' is {new { name.Length }}");
// you can also specify other property names
logger.InformationInterpolated($"length of name '{new { userName = name }}' is {new { lengthOfName = name.Length }}");
来源：https://stackoverflow.com/questions/61816775/c-sharp-serilog-how-to-log-with-string-interpolation-and-keep-argument-names-in