添加Serilog文件日志;

更改空blob列插入规则，现在将插入空blob而不是NULL;

ConsoleApp2/Program.cs

@@ -12,6 +12,7 @@ using Microsoft.Extensions.Logging;
 using MySqlConnector;
 using Serilog;
 using Microsoft.Extensions.Caching.Distributed;
+using Serilog.Events;
 
 
 await RunProgram();
@@ -471,7 +472,12 @@ async Task RunProgram()
     host.Services.AddLogging(builder =>
     {
         builder.ClearProviders();
-        builder.AddSerilog(new LoggerConfiguration().WriteTo.Console().CreateLogger());
+        builder.AddSerilog(new LoggerConfiguration()
+            .WriteTo.Console()
+            .WriteTo.File("./log/error.log", restrictedToMinimumLevel:LogEventLevel.Error)
+            // .WriteTo.File("./log/info.log", restrictedToMinimumLevel:LogEventLevel.Information) //性能考虑暂不使用
+            .CreateLogger()
+        );
     });
 
     host.Services.AddSingleton<ProcessContext>();