TDBEdit.KeyDown

Handles key down events in the control.

Declaration

Source position: dbctrls.pp line 193

Arguments

Description

KeyDown is an overridden method in TDBEdit. KeyDown calls the inherited method, and ensures that the specified virtual key code and modifier are applied in the manner needed for the data-aware control. KeyDown handles the following virtual key codes:

VK_ESCAPE

Cancels an active edit and resets the state for the DataSource. Calls the Reset method in the internal TFieldDataLink, and re-selects the content in the control. Sets Key to the value VK_UNKNOWN.

VK_DELETE or VK_BACK

Sets the value in Key to VK_UNKNOWN when the control is used on a field that cannot be edited.

VK_RETURN

Calls the UpdateRecord method in the internal TFieldDataLink instance when it is in an edit state.

For the macOS (Darwin) platform, additional virtual key codes are detected (and discarded) if the contents of the field in the linked dataset cannot be modified. These keys include:

VK_0..VK_9

numeric characters not on the numeric keypad

VK_A..VK_Z

alphabetic characters

VK_SPACE

space character

VK_NUMPAD0..VK_NUMPAD9

numeric digits on the numeric keypad

VK_MULTIPLY, VK_DIVIDE, VK_ADD, VK_SUBTRACT

operators on the numeric keypad

VK_SEPARATOR, VK_DECIMAL

padded and non-padded Decimal separators

VK_OEM_1

';:' keycap on the US standard keyboard

VK_OEM_2

'/?' keycap on the US standard keyboard

VK_OEM_3

'`~' keycap on the US standard keyboard

VK_OEM_4

'[{' keycap on the US standard keyboard

VK_OEM_5

'\|' keycap on the US standard keyboard

VK_OEM_6

']}' keycap on the US standard keyboard

VK_OEM_7

''"' (Apostrophe and Quote) keycap on the US standard keyboard

VK_OEM_8

miscellaneous character; varies by keyboard layout

For these macOS-specific keys, the value in Key is set to 0 if the field cannot be modified.

Version info

Modified in LCL version 3.6 to handle additional data keys on the macOS (Darwin) platform.

See also