在.NET Core3.1Web API单元测试中运行IApplicationBuilder时扩展/定制TestServer

public class TestStartup : Startup
{
    public TestStartup(IConfiguration configuration) : base(configuration)
    {
    }

    public override void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        // 添加自定义的中间件和服务配置
        // app.UseMiddleware<CustomMiddleware>();
        // app.UseCustomService();

        base.Configure(app, env);
    }
}

[TestClass]
public class MyControllerTests
{
    private readonly TestServer _server;
    private readonly HttpClient _client;

    public MyControllerTests()
    {
        var webHostBuilder = new WebHostBuilder()
            .UseStartup<TestStartup>(); // 使用自定义的TestStartup类

        _server = new TestServer(webHostBuilder);
        _client = _server.CreateClient();
    }

    [TestMethod]
    public async Task Get_EndpointReturnsSuccessAndCorrectContentType()
    {
        // 发送请求并验证响应
        var response = await _client.GetAsync("/api/mycontroller");
        response.EnsureSuccessStatusCode();
        Assert.AreEqual("application/json", response.Content.Headers.ContentType.ToString());
    }

    // 其他测试方法...
}