ASP.NET Core的日志系统介绍

var service = new ServiceCollection()
    .AddLogging(logging => { logging.AddConsole(); });
 
var provider   = service.BuildServiceProvider();
var logFactory = provider.GetService<ILoggerFactory>();
var logger     = logFactory.CreateLogger("MyLogger");
 
logger.LogInfORMation("hello world. {0}", DateTime.Now);

var logger = logFactory.CreateLogger<Program>();

var logger = logFactory.CreateLogger(typeof(Program).FullName);

var logger = provider.GetService<ILogger<Program>>();

var service = new ServiceCollection()
    .AddLogging(logging => { logging.AddConsole(); });
 
var provider   = service.BuildServiceProvider();
var logFactory = provider.GetService<ILoggerFactory>();
var logger     = logFactory.CreateLogger("MyLogger");
 
logger.LogInformation("hello world. {0}", DateTime.Now);

{
    "Logging": { 
        "LogLevel": { // 表示全局 
            "Default": "Warning" // 不指定CateGoryName，应用于所有Category 
        },
        "Console": { // 指定 ProviderName，仅针对于 ConsoleProvider 
            "Default": "Warning",
            "Microsoft": "Error" // 指定CategoryName为Microsoft的日志级别为Error
        }
    }
}

var configBuilder = new ConfigurationBuilder().AddJSONFile("appsettings.json");
var config        = configBuilder.Build();

var service = new ServiceCollection()
    .AddLogging(logging =>
    {
        logging.AddConfiguration(config.GetSection("Logging"));
        logging.AddConsole();
    });