用SQL列填充WPF组合框

<ComboBox x:Name="comboBox" ItemsSource="{Binding}">
    <ComboBox.ItemTemplate>
        <DataTemplate>
            <TextBlock Text="{Binding}" />
        </DataTemplate>
    </ComboBox.ItemTemplate>
</ComboBox>

using (SqlConnection connection = new SqlConnection(connectionString))
{
    connection.Open();
    SqlCommand command = new SqlCommand("SELECT columnName FROM tableName", connection);
    SqlDataReader reader = command.ExecuteReader();
    List<string> items = new List<string>();
    while (reader.Read())
    {
        items.Add(reader.GetString(0));
    }
    comboBox.ItemsSource = items;
}