How do I get actual name of checkbox instead of datarowview

How do I loop through all checkboxes loaded by

public void loadTags()
    {
        DataTable dt = new DataTable();
        using (SqlCommand selectTags = new SqlCommand("select tag from Categories", cs))
        {
            cs.Open();
            using (SqlDataAdapter dataAd = new SqlDataAdapter(selectTags))
            {
                dt = new DataTable();
                dataAd.Fill(dt);
            }
            cs.Close();
        }
        list1.ItemsSource = dt.DefaultView;  
    }

xaml:

<ListView Name="list1" HorizontalAlignment="Left" VerticalAlignment="Top" Margin="307,52,0,0" Height="132" Width="293">
   <ListView.ItemTemplate>
       <DataTemplate>
          <CheckBox Content="{Binding tag}"/>
       </DataTemplate>
   </ListView.ItemTemplate>
  </ListView>

do you have any idea how do I get now all tag names (checkboxes) using loop?

If I hardcode these checkboxes straight into grid this loop is working. But if I get them straight from the database i only get System.Data.DataRowView instead of spo, inf, war etc if these checkboxes are checked.

foreach (var items in list1.Items)
        {
            if (items.IsChecked == true)
            {
                list.Add("CategoryMulti like '%" + item.Content.ToString() + "%'");
            }
        }