Maximum Filesize of LogFileAppender in Log4Net

The FileAppender class does not have the MaxFileSize/MaximumFileSize properties. You only get those if you use a RollingFileAppender. Here’s an example that will limit your file to a fixed maximum size, with no backups (set maxSizeRollBackups to 0). Note that when the file reaches its max size, it truncates (basically deletes all existing logging and starts over):

<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
    <file value="log.txt" />
    <appendToFile value="true" />
    <rollingStyle value="Size" />
    <maxSizeRollBackups value="0" />
    <maximumFileSize value="10MB" />
    <staticLogFileName value="true" />
    <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
    </layout>
</appender>