您可以将IConfigurationRoot注入到可以在测试项目中使用本地配置文件的位置.您将丢失默认的特定于环境的配置替代，这是新项目模板中的默认替代，但是我个人无论如何都不会将其用于配置管理(建议使用非承诺的appsetting.local.json，这对于开发人员而言是唯一的)并连接到CI服务器.

You could just inject the IConfigurationRoot where you could just use a local config file in the test project. You'd lose the default environment-specific config overrides that are the default in the new project template, but I personally don't use those for configuration management anyway (preferring non-committed appsetting.local.json instead which can be unique to developers and to the CI server).

var configuration = new ConfigurationBuilder()
    .SetBasePath(AppContext.BaseDirectory)
    .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
    .AddJsonFile("appsettings.local.json", optional: true, reloadOnChange: true)
    .AddInMemoryCollection(new Dictionary<string, string>
    {
        {"myConfig:setting1", "value1"},
        {"myConfig:setting2", "value2"}
    })
    .Build();

var server = new TestServer(new WebHostBuilder()
    .UseUrls("http://localhost:5001")
    .UseContentRoot(Directory.GetCurrentDirectory())
    .UseStartup<Startup>()
    .ConfigureServices(services => services.AddSingleton(configuration)));

对于启动:

public class Startup
{
    public Startup(IConfigurationRoot configuration)
    {
        this.Configuration = configuration;
    }

    ...
}

修改: 尽管这确实可行，但似乎也无法在运行时识别配置文件更改，从而中断了IOptionsSnapshot配置注入.我将离开这个答案，但也将继续挖掘更好的方法，而无需注入自定义服务来仅支持测试/夹具特定的配置替代.

While this does work, it also seems to break IOptionsSnapshot configuration injections from recognizing config file changes at run-time. I'm going to leave this answer, but will also keep digging for better way without injecting a custom service just to support test/fixture-specific config overrides.