WPF：C#如何获取列表框的选定值？

Question

I am trying to fetch the selected value of the listbox. When I actually try LstGroup1.SelectedItem I get the value { BoothID = "4", BoothName = "HP" } and even if i try to get the value from LstGroup1.SelectedValue the output is same. Now I want to fetch BoothID ie the expected output is 4 but i am unable to get so.

My ListBox name is LstGroup1 .

public List<object> BoothsInGroup1 { get; set; }
// Inside the Constructor 
BoothsInGroup1 = new List<object>();
//After Fetching the value add 
BoothsInGroup1.Add(new { BoothID = da["BoothID"].ToString(), BoothName = da["BoothName"].ToString() });

//Now here I get 
var Booth = (LstGroup1.SelectedItem);
//Output is { BoothID = "4", BoothName = "HP" }

// Expected Output 4

Suggest me how to do that.

---

EDIT

public partial class VotingPanel : Window
{
    public List<object> BoothsInGroup1 { get; set; }
    public VotingPanel()
    {
        InitializeComponent();
        DataContext = this;
        BoothsInGroup1 = new List<object>();

        //Connection is done
        SqlConnection con = new SqlConnection(ConnectionString);
        con.Open();

        FieldNameCmd.CommandText = "SELECT * FROM Booth b, BoothGroup bg where bg.GroupID=b.GroupID;";
        IDataReader da = FieldNameCmd.ExecuteReader();
        while (da.Read())
        {
            if (Group1Name.Text == da["GroupName"].ToString())
            { // Adds value to BoothsInGroup1
                BoothsInGroup1.Add(new { BoothID = da["BoothID"].ToString(), BoothName = da["BoothName"].ToString() });
            }
        }
    }
    private void BtnVote_Click(object sender, RoutedEventArgs e) // on Click wanted to find the value of Selected list box
    {   
        if (LstGroup1.SelectedIndex >= 0 && LstGroup2.SelectedIndex >= 0)
        {
            var Booth = (LstGroup1.SelectedItem);
            //Few things to do 
        }
    }
}

XAML

<ListBox Grid.Row="1"
         Name="LstGroup1"
         ItemsSource="{Binding BoothsInGroup1}"
         Margin="5,1">
    <ListBox.ItemTemplate>
        <DataTemplate>
            <Grid Margin="5">
                <Grid.ColumnDefinitions>
                    <ColumnDefinition />
                    <ColumnDefinition />
                </Grid.ColumnDefinitions>
                <TextBlock Text="{Binding BoothID}"
                           HorizontalAlignment="Center"
                           VerticalAlignment="Bottom"
                           FontSize="15"
                           FontWeight="ExtraBold"
                           Margin="5,3"
                           Grid.Column="1" />
                <TextBlock Text="{Binding BoothName}"
                           Grid.Column="1"
                           VerticalAlignment="Center"
                           FontWeight="ExtraBold"
                           FontSize="30"
                           Margin="15" />

            </Grid>
        </DataTemplate>
    </ListBox.ItemTemplate>
</ListBox>

Answer 1

since you are using anonymous type to populate the listbox, so you have left with no option then an object type to cast the SelectedItem to. other approach may include Reflection to extract the field/property values.

but if you are using C# 4 or above you may leverage dynamic

    if (LstGroup1.SelectedIndex >= 0 && LstGroup2.SelectedIndex >= 0)
    {
        //use dynamic as type to cast your anonymous object to
        dynamic Booth = LstGroup1.SelectedItem as dynamic;
        //Few things to do 

        //you may use the above variable as
        string BoothID = Booth.BoothID;
        string BoothName = Booth.BoothName:

    }

this may solve your current issue, but I would suggest to create a class for the same for many reasons.

Answer 2

Have you tried :

var Booth = (LstGroup1.SelectedItem);
string ID=Booth.BoothID;
string Name=Booth.BoothName:

Answer 3

I think, you should try one of the following : //EDIT : This solution only works, if Booth is a class/struct

var myBooth = LstGroup1.SelectedItem as Booth;
String id =myBooth.BoothID;
String name=myBooth.BoothName:

or use a generic list with a different type :

public List<Booth> BoothsInGroup1 { get; set; }
....
var myBooth = LstGroup1.SelectedItem;
String id =myBooth.BoothID;
Stringname=myBooth.BoothName:

And if Booth isn't a class yet, add a new class:

public class Booth
{
    public int BoothID { get; set; }
    public String BoothName { get; set; }
}

So u can use it in your generic list, an you can fill it after databasereading

BoothsInGroup1.Add(new Booth
   { 
     BoothID = Convert.ToInt32(da["BoothID"]),
     BoothName = da["BoothName"].ToString() 
   });

Answer 4

You can always create a class called Booth to get the data in the Object Format. From My point of view Dynamic is not the right way of doing this. Once you have the Class Booth in the Solution you can run

Booth Booth1 = LstGroup1.SelectedItem as Booth;
string BoothID1 = Booth1.BoothID;

Answer 5

public List<object> BoothsInGroup1 { get; set; }

BoothsInGroup1 = new List<object>();

BoothsInGroup1.Add(new { BoothID = da["BoothID"].ToString(), BoothName = da["BoothName"].ToString() });


var Booth = (LstGroup1.SelectedItem);
var output = Booth.BoothID;

Answer 6

For those that know the type or object that they want the code will look like this:

private void lboxAccountList_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
      //Class object = (Class)listName.SelectedItem;
      // object.getName or object.getSomeVariable or object.callMethod(object.getName)

      Account account  = (Account)lboxAccountList.SelectedItem;
      MessageBox.Show(""+account.AccountNo+" "+account.Balance);          
}