WPF异步httpclient未返回字符串

using System.Net.Http;

public async Task<string> GetResponseAsync()
{
    HttpClient httpClient = new HttpClient();
    HttpResponseMessage response = await httpClient.GetAsync("https://example.com");
    string result = await response.Content.ReadAsStringAsync();
    return result;
}

using System.Net.Http;

public async Task<string> GetResponseAsync()
{
    try
    {
        HttpClient httpClient = new HttpClient();
        HttpResponseMessage response = await httpClient.GetAsync("https://example.com");
        response.EnsureSuccessStatusCode(); // 确保请求成功
        string result = await response.Content.ReadAsStringAsync();
        return result;
    }
    catch (Exception ex)
    {
        // 处理异常情况
        return ex.Message;
    }
}