PostAsync json 对对象/变量的响应

Question

所以如果我调用（POST）API，我会收到这样的 json 响应：

[
  {
    "datum": "23.04.2023",
    "wert": "400"
  }
]

现在我想在我的程序中存储这两个变量，所以我创建了一个对象

public partial class Root
{
    [JsonProperty("datum")]
    public string datum { get; set; }

    [JsonProperty("wert")]
   // [JsonConverter(typeof(ParseStringConverter))]
    public string wert { get; set; }
}

然后我尝试将 ReadAsString 反序列化为变量，但这不起作用，我没有得到任何值。

        public async void GET_WERT(string url)
          {
            var client = new HttpClient();
            var response = await client.PostAsync(url, null);
            var jsonAsString = await response.Content.ReadAsStringAsync();

//This is not working, the MessageBox is poping out but its empty.
var variables = await response.Content.ReadFromJsonAsync<List<Root>>();
                Root vars = new Root();
MessageBox.Show(vars.wert + vars.datum);

            if (response.IsSuccessStatusCode)
            {
              
            }
            else
            {
//Error handling
            }
            
        }