ASP.NET CORE学习笔记（host主机）

1.ASP.NET CORE学习笔记（host主机）2023-10-19

1、扩展包 Microsoft.Extensions.Hosting

2、包括Host、WebApplication

3、示例

1）honst 注意： <Project Sdk="Microsoft.NET.Sdk">

            var builder = Host.CreateDefaultBuilder(args);
            var app = builder.Build();
            app.Run();

2）webApplictaion 注意：<Project Sdk="Microsoft.NET.Sdk.Web">

            var builder = WebApplication.CreateBuilder(args);
            builder.WebHost.UseUrls("http://localhost:8888/");
            builder.Services.AddControllersWithViews();
            var app = builder.Build();
            app.UseRouting();
            app.MapGet("/", content => content.Response.WriteAsync("hello first!"));
            app.Run();

4、环境变量

dev（开发环境）、SIT（集成环境）、UAT（用户测试）、PRD（生产环境）

            var builder = WebApplication.CreateBuilder(args);
            builder.Configuration.AddJsonFile("test.Json");
            builder.WebHost.UseUrls("http://localhost:8888/");
            var app = builder.Build();
            app.UseRouting();
            app.MapGet("/", content => content.Response.WriteAsync(builder.Environment.EnvironmentName));//获取环境变量
            app.MapGet("/Test", content => content.Response.WriteAsync(builder.Configuration["myValue"].ToString()));//web应用获取配置Json的值
            app.MapGet("/Test1", content => content.Response.WriteAsync(app.Configuration.GetRequiredSection("myValue").Value));
            app.Run();

            var builder = Host.CreateDefaultBuilder(args);
            builder.ConfigureHostConfiguration(option =>
                option.AddEnvironmentVariables("myValue").AddJsonFile("test.Json")
             );//从配置配置环境变量
            var app = builder.Build();
            var config = app.Services.GetRequiredService<IConfiguration>();
            var logger=app.Services.GetRequiredService<ILogger<Program>>();
            logger.LogInformation(config.GetValue<string>("myValue"));//从配置文件获取环境变量值
            app.Run();