.NET Core(C#) 编写Console控制台程序示例代码

1、编写简单的Console控制台程序

该程序将从命令行读取基本选项，然后在不进行用户交互的情况下执行和终止。

例如，

using System;using System.Threading.Tasks;using Microsoft.Extensions.DependencyInjection;using Microsoft.Extensions.Hosting;using Microsoft.Extensions.Logging;namespace PackWidgetTemplate{    class Program    {        static void Main(string[] args)        {            using (var host = CreateHostBuilder(args).Build())            {                await host.StartAsync();                var lifetime = host.Services.GetRequiredService();                // 写需要执行的代码                lifetime.StopApplication();                await host.WaitForShutdownAsync();            }        }        private static IHostBuilder CreateHostBuilder(string[] args) =>     Host.CreateDefaultBuilder(args)         .UseConsoleLifetime()         .ConfigureLogging(builder => builder.SetMinimumLevel(LogLevel.Warning))         .ConfigureServices((hostContext, services) =>         {             services.Configure(hostContext.Configuration);             services.AddHostedService();             services.AddSingleton(Console.Out);         });    }}

2、编写一般Console控制台程序

Program.cs：

using System;using System.Threading.Tasks;using Microsoft.Extensions.DependencyInjection;using Microsoft.Extensions.Hosting;using Microsoft.Extensions.Logging;namespace MyApp{    public static class Program    {        public static async Task Main(string[] args)        {            await CreateHostBuilder(args).RunConsoleAsync();        }        private static IHostBuilder CreateHostBuilder(string[] args) =>            Host.CreateDefaultBuilder(args)                .UseConsoleLifetime()                .ConfigureLogging(builder => builder.SetMinimumLevel(LogLevel.Warning))                .ConfigureServices((hostContext, services) =>                {                    services.Configure(hostContext.Configuration);                    services.AddHostedService();                    services.AddSingleton(Console.Out);                });    }}

MyServiceOptions.cs：

namespace MyApp
{
    public class MyServiceOptions
    {
        public int OpCode { get; set; }
        public int Operand { get; set; }
    }
}

MyService.cs：

using System.IO;using System.Threading;using System.Threading.Tasks;using Microsoft.Extensions.Hosting;using Microsoft.Extensions.Options;namespace MyApp{    public class MyService : IHostedService    {        private readonly MyServiceOptions _options;        private readonly TextWriter _outputWriter;        public MyService(TextWriter outputWriter, IOptions options)        {            _options = options.Value;            _outputWriter = outputWriter;        }        public async Task StartAsync(CancellationToken cancellationToken)        {            _outputWriter.WriteLine("Starting work");            DoOperation(_options.OpCode, _options.Operand);            _outputWriter.WriteLine("Work complete");        }        public async Task StopAsync(CancellationToken cancellationToken)        {            _outputWriter.WriteLine("StopAsync");        }        protected void DoOperation(int opCode, int operand)        {            _outputWriter.WriteLine("Doing {0} to {1}...", opCode, operand);            // 执行可能耗时的代码        }    }}