public static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureLogging((context,ILoggingBuilder)=> {
                    ILoggingBuilder.AddFilter("System", LogLevel.Warning);
                    ILoggingBuilder.AddFilter("Microsoft", LogLevel.Warning);
                    ILoggingBuilder.AddLog4Net();
                })
                .ConfigureWebHostDefaults(webBuilder =>
                {
                    webBuilder.UseStartup<Startup>();
                });

<?xml version="1.0" encoding="utf-8" ?>
<log4net>
    <appender name="DebugAppender" type="log4net.Appender.DebugAppender" >
        <layout type="log4net.Layout.PatternLayout">
            <conversionPattern value="%date [%thread] %-5level %logger - %message%newline" />
        </layout>
    </appender>
    <!--指定日记记录方式，以滚动文件的方式（文件记录）-->
    <appender name="RollingFile" type="log4net.Appender.RollingFileAppender">
        <!--日志路径-->
        <file value="log\log.txt" />
        <!--是否是向文件中追加日志-->
        <appendToFile value="true" />
        <!--log保留天数-->
        <param name= "MaxSizeRollBackups" value= "10"/>
        <!--每个文件最大1M-->
        <param name="maximumFileSize" value="1MB" />
        <!--日志根据日期滚动-->
        <param name="RollingStyle" value="Date" />
        <!--日志文件名格式为:logs_20080831.log-->
        <param name="DatePattern" value="&quot;logs_&quot;yyyyMMdd&quot;.log&quot;" />
        <!--日志文件名是否是固定不变的-->
        <param name="StaticLogFileName" value="false" />
        <!--布局-->
        <layout type="log4net.Layout.PatternLayout">
            <conversionPattern value="%date %5level %logger.%method [%line] - MESSAGE: %message%newline %exception" />
        </layout>
    </appender>
    <root>
        <level value="ALL"/>
        <appender-ref ref="DebugAppender" />
        <appender-ref ref="RollingFile" />
    </root>
</log4net>