C#中类的引用和套用

// See https://aka.ms/new-console-template for more information
namespace Helloworld
{
    class Logger
    {
        public void Log(string message) {
            Console.WriteLine($"日志：{DateTime.Now} - {message}");
        }
    }
}

// See https://aka.ms/new-console-template for more information
namespace Helloworld
{
    class Install
    {
        private readonly Logger logger;

        public Install(Logger logger)
        {
            this.logger = logger;
        }
        public void install()
        {
            logger.Log("安装开始");
        }
    }
}

// See https://aka.ms/new-console-template for more information
namespace Helloworld
{
    class DbMigrator
    {
        private readonly Logger _logger;
        public DbMigrator(Logger logger)
        {
            _logger = logger;
        }
        public void Migrate()
        {
            _logger.Log("数据迁移开始");
        }
    }
}

// See https://aka.ms/new-console-template for more information
namespace Helloworld
{
    class Program
    {
        static void Main(string[] args)
        {
            var logger = new Logger();
            var dbMigrate = new DbMigrator(logger);
            var install = new Install(logger);
            install.install();
            dbMigrate.Migrate();
            Console.WriteLine();
        }
    }
}