Configure log4net RollingFileAppender to roll on size but append datetime?

Question

I want to configure my log4net Rolling log appender such that the name of my initial log file is:-

log_{current_datetime}.log

When the file reaches 25MB size , a new log file should be created with the same format and the previous log file should not be renamed.

How do I do such a setting on log4net appender?

Answer 1

Use a PatternString for the filename:

<file type="log4net.Util.PatternString" value="log_%date{yyyyMMdd}.log" />

In order to configure rolling on size, make sure you specify RollingStyle and MaximumFileSize:

<rollingStyle value="Size"/>
<maximumFileSize value="25MB"/>

Full examples can be found here.

Update:

Unfortunately, the date specified in the filename is only evaluated upon configuration, meaning the same date will be used on each roll until log4net is reconfigured. I have not found a way to fix this.