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TDBComboBox Control

TDBComboBox

Description

Represents a data-aware combo box control.

Remarks

Use TDBComboBox to allow users to change the value of a field on the current record in a dataset either by selecting an item from a list or by typing in the edit box part of the control. The selected item or entered text becomes the new value of the field if the database combo box's ReadOnly property is false. The combo box can be customized to enable or disable typing in the edit region of the control, to display the list as a drop down or as a permanently displayed list, to sort the items in the list, and so on.

TDBComboBox Properties

Property Property Items: TStringList (R)

Contains the strings that appear in the list of the database combo box. Use Items to supply the values in the list from which the user can choose. Because Items is an object of type TStringList, you can add, delete, insert items using the Add, Delete, Insert methods of the TStringList object.

Property Property Style: Enumerated(R/W)

Determines how the combo box displays its items. Use Style to specify whether the user can type values into the edit region as well as select values from the list, whether the list drops down when the user clicks a button or if it is always displayed and so on. By default, Style is csDropDown, meaning that the combo box displays each item as a string in a drop-down list, and that users can edit the value in the edit region. Style can be any of the values: csDropDown, csSimple, csDropDownList.

General Data-Aware Control Properties

Property Property DataField: String (R/W)

Property Property DataSource: TDataSource (R/W)

Property Property ReadOnly: Boolean (R/W)