列表框未显示反序列化的JSON数据

Question

I came across this problem for days , I couldnt solve it. The listbox in my windows phone is not displaying anything. I am not even sure whether the json deser works.

A json sample code is inside within the c# code commented.

This is the part of C# in WP8

private void Button_Click_1(object sender, RoutedEventArgs e)
{
    webserv.maintain_serverPortTypeClient tables = new webserv.maintain_serverPortTypeClient();
    tables.view_tableAsync();
    tables.view_tableCompleted += new EventHandler<webserv.view_tableCompletedEventArgs>(tbviewcomplete);
}

public void tbviewcomplete(object obj, webserv.view_tableCompletedEventArgs e)
{
    MessageBox.Show(e.Result.ToString());
    // var table_json = e.Result.ToString();

    // var table_json = "[{\"tableID\":\"61\",\"size\":\"4\",\"zone\":\"Non-Smoking\",\"area\":\"Outdoor\"},{\"tableID\":\"62\",\"size\":\"4\",\"zone\":\"Non-Smoking\",\"area\":\"Outdoor\"},{\"tableID\":\"63\",\"size\":\"4\",\"zone\":\"Smoking\",\"area\":\"Indoor\"},{\"tableID\":\"64\",\"size\":\"30\",\"zone\":\"Smoking\",\"area\":\"Indoor\"}]";
    //   MyTables[] result = JsonConvert.DeserializeObject<MyTables[]>(table_json);

    List<MyTables> gesult = JsonConvert.DeserializeObject<List<MyTables>>(e.Result);
    tableview.ItemsSource = gesult;
}

public class MyTables
{
    public string table_id { get; set; }
    public string table_size { get; set; }
    public string table_zone { get; set; }
    public string table_area { get; set; }
}

And this is the part of the XAML code.

<ListBox x:Name="tableview" ItemsSource="{Binding data}" HorizontalAlignment="Left"     Height="474" VerticalAlignment="Top" Width="456">
 <ListBox.ItemTemplate>
                        <DataTemplate>
                            <StackPanel DataContext="{Binding}">
                                <TextBlock FontSize="{StaticResource PhoneFontSizeMedium}" Text="{Binding table_id}" />
                                <TextBlock Text="{Binding table_size}" />
                                <TextBlock Text="{Binding table_zone}" />
                                <TextBlock Text="{Binding table_area}" />
                            </StackPanel>
                        </DataTemplate>
 </ListBox.ItemTemplate>


</ListBox>

I do not know where went wrong and it doesnt display. Please drop me down some advice. I am very new to c# and Json.

Answer 1

For doing what you want, first either you must use the exact field names used in JSON string or use System.Runtime.Serialization.DataContract and System.Runtime.Serialization.DataMember attributes to decorate MyTable class and its properties in order to use arbitrary property names. So MyTable class would look like this without contract:

public class MyTable
{
    public string tableID { get; set; }
    public int size { get; set; }
    public string zone { get; set; }
    public string area { get; set; }
}

or like this with DataContract :

using System.Runtime.Serialization;

...

[DataContract]
public class MyTable
{
    [DataMember(Name = "tableID")]
    public string table_id { get; set; }

    [DataMember(Name = "size")]
    public int table_size { get; set; }

    [DataMember(Name = "zone")]
    public string table_zone { get; set; }

    [DataMember(Name = "area")]
    public string table_area { get; set; }
}

Note that, JSON field name can be specified using Name property of DataMember attribute. This way, you can use any property name in your class MyTable .

Then, use this to deserialize your JSON string:

System.Runtime.Serialization.Json.DataContractJsonSerializer ser = new System.Runtime.Serialization.Json.DataContractJsonSerializer(typeof(List<MyTable>));
string table_json = e.Result.ToString();
List<MyTable> result;
using (System.IO.MemoryStream ms = new System.IO.MemoryStream(Encoding.UTF8.GetBytes(table_json)))
{
    result = (List<MyTable>)ser.ReadObject(ms);
}

Note that you must add System.Runtime.Serialization.dll to your project references.

Answer 2

XAML

<Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
            <ListBox x:Name="MyListBox">
                <ListBox.ItemTemplate>
                    <DataTemplate>
                        <StackPanel Orientation="Horizontal">
                            <TextBlock Text="{Binding Artist}"/>
                            <TextBlock Text="{Binding Duration}"/>
                        </StackPanel>
                    </DataTemplate>
                </ListBox.ItemTemplate>
            </ListBox>
        </Grid>

and C# code:

public class MyDataClass
{
    public string Artist { get; set; }
    public string Duration { get; set; }

    public MyDataClass(string artist, int duration)
    {
        TimeSpan span = TimeSpan.FromSeconds(duration);
        Artist = artist;
        Duration = span.ToString();
    }
}

public void AudioGet()
{
    var clientAudio = new WebClient();
    clientAudio.OpenReadCompleted += clientAudio_OpenReadCompleted;
    string uri = "https://api.vk.com/method/audio.get?";
    clientAudio.OpenReadAsync(new Uri(uri));
}

private void clientAudio_OpenReadCompleted(object sender, OpenReadCompletedEventArgs e)
{
    List<MyDataClass> audioList = new List<MyDataClass>();
    var root = new DataContractJsonSerializer(typeof(RootObject));
    RootObject rootObject = (RootObject)root.ReadObject(e.Result);

    foreach (var myClass in rootObject.response)
    {
        audioList.Add(new MyDataClass(myClass.artist, myClass.duration));
    }

    MyListBox.ItemsSource = audioList;
}

#region JsonDataClass
public class Response
{
    public string artist { get; set; }
    public int duration { get; set; }
}

public class RootObject
{
    public List<Response> response { get; set; }
}
#endregion