如何在控制台应用程序中获取依赖项注入的IConfiguration

dotnet new console -o ConsoleAppWithDI
cd ConsoleAppWithDI

using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;

class Program
{
    static void Main(string[] args)
    {
        // 创建服务集合
        var services = new ServiceCollection();

        // 添加 IConfiguration
        var configuration = new ConfigurationBuilder()
            .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
            .AddEnvironmentVariables()
            .Build();

        services.AddSingleton(configuration);

        // 构建服务提供者
        var serviceProvider = services.BuildServiceProvider();

        // 获取 IConfiguration 实例
        var config = serviceProvider.GetService<IConfiguration>();

        // 使用 IConfiguration
        var mySetting = config["MySetting"];
        Console.WriteLine($"MySetting value: {mySetting}");
    }
}

{
  "MySetting": "Hello, World!"
}

dotnet run

MySetting value: Hello, World!

<ItemGroup>
  <None Update="appsettings.json">
    <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
  </None>
</ItemGroup>