ASP。NET Core 3.1-集成测试中的PostAsync/PostAsJsonAsync方法总是返回错误请求

这是我在AuthController中的注册方法。

[HttpPost(ApiRoutes.Auth.Register)]
public async Task<IActionResult> Register(UserRegistrationRequest request)
{
    var authResponse = await _authService.RegisterAsync(request.Email, request.Password);

    if (!authResponse.Success)
    {
        return BadRequest(new AuthFailedResponse
        {
            Errors = authResponse.Errors
        });
    }

    return Ok(new AuthSuccessResponse
    {
        Token = authResponse.Token,
        RefreshToken = authResponse.RefreshToken
    });
}

我试图通过以下方式调用此方法 TestClient.PostAsync() 方法,不幸的是,它总是返回Bad Request。我已经试着打电话给 TestClient.PostAsJsonAsync(ApiRoutes.Auth.Register, user) 方法通过导入 Microsoft.AspNet.WebApi.Client 包,结果是一样的。

var user = new UserRegistrationRequest
    {
        Email = "user1@testtest.com",
        Password = "P@ssw0rd1!!!!!"
    };

var response = await TestClient.PostAsync(
        ApiRoutes.Auth.Register,
        new StringContent(JsonConvert.SerializeObject(user), Encoding.UTF8)
        {
            Headers = { ContentType = new MediaTypeHeaderValue("application/json") }
        });