Press Enter key, then Combobox clear text, how to stop it ?

[QuangNhat]

Hi,
I use Combobox in DropDownStyle = simple, and AutoCompleteMode, I bind DataSource for Combobox. So I have a Combobox AutoComplete with a list from Database.
When I use in DropDownStyle = DropDownList, it don't have problem.
But when I use it in Simple, when I chose a item by press Enter, Text of Combobox is cleared. I use PreviewKeyDown and set again text for Combobox. But there are 2 times occur this event, and text is set 1 times, then it is cleared.
Please help me solve this problem. Thanks.
I post 4 images. First image is I chose item.
Second image is PreviewKeyDown occur first time.
Third image is set Text of Combobox (it is cleared).
Fourth image is PreviewKeyDown occur again, then Text is cleared.

[QuangNhat]

:), I have just find the answer, I add a command, result:

if (e.KeyValue == 13)
            {
                if (Combobox.Text != "")
                    StringGlobal = Combobox.Text;
                if (Combobox.Text == "")
                    Combobox.Text = StringGlobal;
            }

But I use mouse to chose the item, text is cleared.

[RhysW]

i would say you aren't using the autocomplete properly then if its deleting everything

[QuangNhat]

I want to create a input (input commands) that it have a function like intellsense. I have found on internet and I found 2 ways: use rich textbox + custom code (harder) and autocomplete combobox.
My combobox (more important properties):
AutoCompleteMode = SuggestAppend
AutoCompleteSource = ListItems
DropDownStyle = Simple
DataSource = MyDataBindingSource
My combobox display a list of commands. When user type, it show commands follow character is typed.
If who can have a solution for my problem, I thank you.