My coding as below but it didn't display member as SuggestAppend it display only base on ComboBox width.
'Private Sub dgvList_EditingControlShowing(ByVal sender As System.Object, ByVal e As ' 'System.Windows.Forms.DataGridViewEditingControlShowingEventArgs) Handles dgvList.EditingControlShowing
' Dim comboBox As ComboBox = CType(e.Control, ComboBox)
' If (comboBox IsNot Nothing) Then
' comboBox.DropDownStyle = ComboBoxStyle.DropDown
' comboBox.AutoCompleteMode = Windows.Forms.AutoCompleteMode.SuggestAppend
' comboBox.AutoCompleteSource = Windows.Forms.AutoCompleteSource.ListItems
' End If
'End Sub