How to customize ComboBoxAutoComplete control's DropDown width?
You can customize the ComboBoxAutoComplete width by using the DropDownWidth property.
The following code example demonstrates the same.
C#
//Specifies the default DropDown width of the ComboBoxAutoComplete. this.comboBoxAutoComplete1.DropDownWidth = this.comboBoxAutoComplete1.Width;
VB
'Specifies the default DropDown width of the ComboBoxAutoComplete. Me.comboBoxAutoComplete1.DropDownWidth = Me.comboBoxAutoComplete1.Width

Figure 1: Before specifying the DropDown width for the ComboBoxAutoComplete

Figure 2: After specifying the default DropDown width for the ComboBoxAutioComplete