McBasic™ 0.7.881 · Build 881 · 11 min read

Controls · Visual control

DatePicker

Distinguish a selected date from a cleared value.

40 properties20 events1 methodsDefault: Change

Build the DatePicker lesson Properties Events Methods

Use it in a Form#

A cleared picker is not the same as today. Keep the date selection and the output label in sync from Change, and use the clear action in the sample to exercise the empty case. Store a date as a date, not as a locale-dependent label.

Add DatePicker to its intended parent and name it dtpDate for this example:

Property	Example value
`Value`	`"2026-01-01"`
`MinimumDate`	`"2023-01-01"`
`MaximumDate`	`"2028-12-31"`
`Format`	`"Custom"`
`CustomFormat`	`"yyyy-MM-dd"`
`IsEmpty`	`False`

A complete handler from Forms/frmMain.bas. The linked lesson includes its surrounding controls, declarations and helpers.

Forms/frmMain.bas

Private Sub dtpDate_Change()
    If dtpDate.IsEmpty Then
        lblStatus.Caption = "No date selected."
    Else
        lblStatus.Caption = "Date changed: " & dtpDate.Value
    End If
End Sub

Properties#

Contract defaults are shown below. Where a new control has a different Designer starting value, that value is listed separately.

`Left`

DoubleDefault: 0

Horizontal position in device-independent points, relative to the parent container.

Range: -100000 to 100000.

`Top`

DoubleDefault: 0

Vertical position in device-independent points, relative to the parent container.

Range: -100000 to 100000.

`Width`

DoubleDefault: 180

Control width in device-independent points.

Range: 0 to 100000.

`Height`

DoubleDefault: 32

Control height in device-independent points.

Range: 0 to 100000.

`MinWidth`

DoubleDefault: 0

Minimum control width in device-independent points; 0 lets the parent layout choose.

Range: 0 to 100000.

`MinHeight`

DoubleDefault: 0

Minimum control height in device-independent points; 0 lets the parent layout choose.

Range: 0 to 100000.

`MaxWidth`

DoubleDefault: 100000

Maximum control width in device-independent points.

Range: 0 to 100000.

`MaxHeight`

DoubleDefault: 100000

Maximum control height in device-independent points.

Range: 0 to 100000.

`TabIndex`

LongDefault: 0

Keyboard navigation order within the parent container; lower values come first.

Range: 0 to 100000.

`ZIndex`

LongDefault: 0

Stacking order among sibling controls; larger values appear in front. Equal values preserve document order.

Range: -100000 to 100000.

`Anchor`

StringDefault: "Left,Top"Not in InspectorNot serialized

Edges kept at their authored distance when the parent resizes. Use a comma-separated combination of Left, Top, Right and Bottom; Dock overrides the effective anchor without deleting it.

`Dock`

StringDefault: "None"

Automatic placement within the parent: None, Left, Top, Right, Bottom or Fill. Dock overrides effective Anchor layout without deleting the stored anchors.

`Visible`

BooleanDefault: True

Whether the control is shown in the running application.

`Font`

StringDefault: ""

DatePicker displayed value font as Family|Size or Family|Size|Regular/Bold|Normal/Italic, size 6–96 DIP. Empty uses the theme font.

`ForeColor`

StringDefault: ""

DatePicker displayed value text color as #RRGGBB. Empty uses the current theme color.

`BackColor`

StringDefault: ""

DatePicker background color as #RRGGBB. Empty uses the current theme background.

`Margin`

StringDefault: "0"

External spacing as one non-negative DIP value or Left,Top,Right,Bottom.

`Cursor`

StringDefault: "Default"

Pointer shown over the control: Default, Arrow, Hand, IBeam, Cross, Wait, Help, SizeAll, SizeNS, SizeWE, SizeNWSE, SizeNESW or NotAllowed.

`Opacity`

DoubleDefault: 1

Visual opacity from 0 (transparent) to 1 (opaque).

Range: 0 to 1.

`DesignLocked`

BooleanDefault: FalseDesigner only

Prevents movement and resizing in the Designer without changing runtime interaction.

`AccessibleDescription`

StringDefault: ""

Additional help text announced by assistive technology.

`AutomationId`

StringDefault: ""

Stable automation identifier; empty uses the component Name.

`AccessibleName`

StringDefault: ""

Name announced by assistive technology. Empty uses the stable control Name.

`AccessibleRole`

StringDefault: "Auto"

Accessibility role override. Auto preserves the native semantic role; explicit values use the corresponding platform automation role.

`ToolTipText`

StringDefault: ""

Help text shown when the pointer rests over the running control; empty disables the tooltip.

`Tag`

StringDefault: ""

Application-defined text associated with this control; McBasic™ does not interpret it.

`Enabled`

BooleanDefault: True

Whether the control accepts user interaction in the running application.

`HitTestVisible`

BooleanDefault: True

Whether the running control participates in pointer hit testing. The control remains selectable in the Designer.

`AllowDrop`

BooleanDefault: False

Whether this running control accepts application drag-and-drop operations; Designer movement is separate.

`DragMode`

LongDefault: 0

VB control drag: 0 Manual (code starts a drag with the Drag method) or 1 Automatic (a left-button press starts a drag, and the control raises no Click, MouseDown or MouseUp for that press).

Range: 0 to 1.

`DragIcon`

StringDefault: ""

Case-insensitive name of a declared project image resource shown under the pointer while this control is dragged; empty shows a grey outline of the control.

`ReadOnly`

BooleanDefault: False

Prevents user text, calendar popup, keyboard and wheel changes while preserving focus, display and BASIC programmatic assignments.

`TabStop`

BooleanDefault: True

Whether Tab navigation can move focus to this DatePicker.

`Value`

StringDefault: ""

Initial calendar date as ISO yyyy-MM-dd text; empty means no date is selected. The BASIC Value member is Date.

`MinimumDate`

StringDefault: "0100-01-01"

Earliest selectable date, serialized as ISO yyyy-MM-dd and exposed to BASIC as Date.

`MaximumDate`

StringDefault: "9999-12-31"

Latest selectable date, serialized as ISO yyyy-MM-dd and exposed to BASIC as Date.

`Format`

StringDefault: "Short"

Displayed date format mode: Short, Long or Custom. Legacy date-pattern values load as Custom.

Designer starting value: "yyyy-MM-dd".

`CustomFormat`

StringDefault: "yyyy-MM-dd"

Custom date pattern used when Format is Custom; retained while another mode is active.

`IsEmpty`

BooleanDefault: True

Whether the calendar has no selected date; empty is distinct from the McBasic™ Date zero value.

`Index`

LongDefault: -1Read only in BASICDesigner Index row

Position of this control in its control array, 0 to 32767. Several controls share one name only when every one of them has an Index. Absent from the layout, and -1 in code, when the control is not in an array.

Designer values: 0 to 32767. Clear the dedicated Index row for a non-array control; BASIC then reads -1.

Events and parameters#

Replace control with the object’s Name when creating a handler. ByRef arguments may be changed by your handler; ByVal arguments report an input value.