根据配置决定绑定端口

asp.net core web项目在开发时根据launchsettings.json中的配置确定绑定的端口和ip地址，在生产环境，缺省端口号是5000和5001，如果想改变，需要使用UseUrls，在Program.cs中增加相应的代码:

        internal static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureAppConfiguration(build =>
                {
                    build.AddJsonFile("appsettings.secrets.json", optional: true);
                })
                .ConfigureWebHostDefaults(webBuilder =>
                {
                    webBuilder.UseStartup<Startup>()
                    .UseUrls("http://0.0.0.0:5000");
                })
                .UseAutofac()
                .UseSerilog();
    }

如果希望使用配置文件设置，需要编写一点额外的代码，从配置文件或者命令行参数中获取需要绑定的地址。扩展的代码如下：

using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using System;

namespace ZL.ServerUrlsExt
{
    public static class CustomServerUrls
    {
        public static IWebHostBuilder UserConfigUrls(this IWebHostBuilder builder, string[] args)
        {
            //增加命令行配置
            var configuration = new ConfigurationBuilder()
            .AddCommandLine(args)
            .AddJsonFile("appsettings.json", optional: true)
            .Build();
            //
            var server = !string.IsNullOrEmpty(configuration["server.urls"]) ? configuration["server.urls"] : "http://0.0.0.0:5000;https://0.0.0.0:5001";
#if DEBUG
            Console.WriteLine(server);
#endif
            return builder.UseUrls(server);

        }
    }
}

使用时将UseUrls改为UseConfigUrls，传入参数改为从命令行接收的参数args:

        internal static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureAppConfiguration(build =>
                {
                    build.AddJsonFile("appsettings.secrets.json", optional: true);
                })
                .ConfigureWebHostDefaults(webBuilder =>
                {
                    webBuilder.UseStartup<Startup>()
                    .UserConfigUrls(args);
                })
                .UseAutofac()
                .UseSerilog();
    }