我正在尝试使用. NET MAUI实现一个小应用程序，但在运行时不断出现错误
System.Net.WebException:无法解析主机"http：//www.example.com"：没有与主机名关联的地址reqres.in": No address associated with hostname'
有时我收到的错误听起来像：
System.InvalidCastException:'指定的转换无效。'
为了显示响应，我使用了ListView控件，最后使用了CollectionView
我使用Nuget软件包管理器安装了Newtonsoft.Json。
代码隐藏文件包含以下代码：

private const string url = "https://reqres.in/api/users";
private HttpClient _Client = new HttpClient();
private ObservableCollection<User> userCollection;

    protected override async void OnAppearing()
    {
        
        base.OnAppearing();

        var httpResponse = await _Client.GetAsync(url);

        if (httpResponse.IsSuccessStatusCode)
        {
            Response responseData = JsonConvert.DeserializeObject<Response>(await httpResponse.Content.ReadAsStringAsync());
            userCollection = new ObservableCollection<User>(responseData.Users);
            User_List.ItemsSource = userCollection;
        }
    }

public class User
{
    [JsonProperty("id")]
    public int Id { get; set; }

    [JsonProperty("email")]
    public string Email { get; set; }

    [JsonProperty("first_name")]
    public string FirstName { get; set; }

    [JsonProperty("last_name")]
    public string LastName { get; set; }

    [JsonProperty("avatar")]
    public string AvatarURI { get; set; }

    public string FullName
    {
        get { return $"{FirstName} {LastName}"; }
    }
}

public class Response
{
    [JsonProperty("page")]
    public int Page { get; set; }

    [JsonProperty("per_page")]
    public int PerPage { get; set; }

    [JsonProperty("total")]
    public int Total { get; set; }

    [JsonProperty("total_pages")]
    public int TotalPages { get; set; }

    [JsonProperty("data")]
    public ObservableCollection<User> Users { get; set; }
}

XAML文件的内容为：

<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
         xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
         x:Class="TabbedPageTest.TeamMembersPage"
         BackgroundColor="{DynamicResource SecondaryColor}">
  <StackLayout>
    <Label Text="Team Members"/>
    <CollectionView x:Name="User_List" HeightRequest="400" >
        <CollectionView.ItemTemplate>
            <DataTemplate>
                <ImageCell ImageSource="{Binding AvatarURI}" Text="{Binding FullName}" Detail="{Binding Email}"/>
            </DataTemplate>
        </CollectionView.ItemTemplate>
    </CollectionView>
    <Button Text="Back" Clicked="OnBackButtonClicked" VerticalOptions="CenterAndExpand" />
  </StackLayout>
</ContentPage>