The standalone GridListControl does not support AutoComplete, but the GirdListControl dropdown that appears in cells does.
If you just want to do a first letter match, you could probably do this by handling the GridListControl.KeyDown event. Here is a little minimal handler that worked for me in our GridListControlSample. (You have to click the control first to it focus. But after that typing a letter takes you to the State Abbreviation.)
private void ListBox1_KeyDown(object sender, KeyEventArgs e)
{
//Console.WriteLine("ListBox1_KeyDown");
int start = this.ListBox1.SelectedIndex;
int i = start + 1;
string s = e.KeyCode.ToString();
while (i > 0 && i < this.ListBox1.Grid.RowCount)
{
if(this.ListBox1.Grid[i + 1, 1].Text.StartsWith(s))
{
this.ListBox1.SelectedIndex = i;
return;
}
i += 1;
}
i = 0;
while(i < start)
{
if(this.ListBox1.Grid[i + 1, 1].Text.StartsWith(s))
{
this.ListBox1.SelectedIndex = i;
return;
}
i += 1;
}
}