C# Serilog: How To Log With String Interpolation And Keep Argument Names In Message Templates?

Answer :

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 }}");