private void setAutocompleteForTextBox() { string[] categories = Units.GetAllCategoriesDescription(); listViewCategory.Clear(); foreach (string s in categories) { listViewCategory.Items.Add(s); } AutoCompleteStringCollection source = new AutoCompleteStringCollection(); Array Values = System.Enum.GetValues(typeof(Units.UnitNamesEnum)); foreach (Units.UnitNamesEnum value in Values) { source.Add(Units.GetUnitSymbol(value)); } textBoxUnit.AutoCompleteCustomSource = source; }