Question

I have the following code, which basically takes values from a database and populates a listview.

using (IDataReader reader = cmd.ExecuteReader())
{                    
    lvwMyList.Items.Clear();
    while (reader.Read())
    {
        ListViewItem lvi = lvwMyList.Items.Add(reader["Value1"].ToString());
        lvi.SubItems.Add(reader["Value2"].ToString());                    
    }
}

The problem that I have is that this is repeatedly executed at short intervals (every second) and results in the items in the listview continually disappearing and re-appearing. Is there some way to stop the listview from refreshing until it’s done with the updates? Something like below:

using (IDataReader reader = cmd.ExecuteReader())
{                    
    lvwMyList.Items.Freeze(); // Stop the listview updating
    lvwMyList.Items.Clear();
    while (reader.Read())
    {
        ListViewItem lvi = lvwMyList.Items.Add(reader["Value1"].ToString());
        lvi.SubItems.Add(reader["Value2"].ToString());                    
    }
    lvwMyList.Items.UnFreeze(); // Refresh the listview
}

Answer 1

Like this:

try
{
    lvwMyList.BeginUpdate();
    //bla bla bla

}
finally
{
    lvwMyList.EndUpdate();
}

Make sure that you invoke lvwMyList.Items.Clear() after BeginUpdate if you want to clear the list before filling it.