在WPF中的组合框中显示MySQL数据库的列？我只显示'System.Data.DataRowView'

Question

我正在尝试获取表格列中的值以填充组合框的选项。每当我尝试时，组合框都会填充正确数量的选项，但不是列的值，而是选项都是'System.Data.DataRowView'。

XAML

<ComboBox x:Name="ComboBox_1" HorizontalAlignment="Left" Margin="124,23,0,0" VerticalAlignment="Top" Width="95" Height="42" ItemsSource="{Binding}"/>

C＃

public MainWindow()
{
    InitializeComponent();
    string connectionString = "SERVER=localhost;DATABASE=dbname; UID=myPC;Password=myPW;";

    mysqlConnection connection = new MySqlConnection(connectionString);

    MySqlCommand cmd = new MySqlCommand("Select columnname from tablename", connection);
    connection.Open();


    DataTable dt = new DataTable();
    dt.Load(cmd.ExecuteReader());
    connection.Close();

    ComboBox_1.DataContext = dt;

}