Log4Net，如何向我的日志中添加自定义字段（变量）

Question

I'm referring to the excellent post :

Log4Net, how to add a custom field to my logging

But it doesn't give me the entire solution.

No problem to log a string like "This is a test", but If I want to log a variable, it's responding (null).

Here is my snipped code not working:

log4net.GlobalContext.Properties["versionid"] = Variables.IDVERSION;

Here is my working snipped code :

log4net.GlobalContext.Properties["versionid"] = " This is a test";

Although, IDVERSION is a public property systematically updated in my code c#.

Has anyone an idea How to solve this problem? I think I'm near the solution.

Answer 1

At the moment you call this:

log4net.GlobalContext.Properties["versionid"] = Variables.IDVERSION;

The property will hold the value of Variables.IDVERSION at that moment . It won't automagically track updates to the Variables.IDVERSION variable.

So if you set Variables.IDVERSION later in code, you need to do the assignment to Properties["versionid"] again.

Answer 2

When log4net evaluates context properties it calls the .ToString() method of the property value. So you could have dynamic property values if you have a reference as a value (I believe your idversion field is a value type eg. Int?).

See https://logging.apache.org/log4net/release/manual/contexts.html for more details