CheckBox Control for Visual Basic 6.0 Users

Artikel
09/03/2015

This topic compares the Visual Basic 6.0 CheckBox control with its equivalent in Visual Basic 2008.

The CheckBox control in Visual Basic 6.0 is replaced by the Windows Forms CheckBox control in Visual Basic 2008. The names of some properties, methods, events, and constants are different, and in some cases there are differences in behavior.

Conceptual Differences

Click Event

In Visual Basic 6.0, the Click event is raised when the CheckBox state is changed programmatically. In Visual Studio 2005 you use the CheckStateChanged event, not the Click event.

Additional Differences

In addition, there are numerous conceptual differences that apply to all controls, including differences in data binding, font handling, drag-and-drop, Help support, and more. For more information, see Windows Forms Overview and Additions to Windows Forms for the .NET Framework 2.0.

Code Changes for the CheckBox Control

The following examples illustrate differences in coding techniques between Visual Basic 6.0 and Visual Basic 2008.

Code Changes for Responding to CheckBox Clicks

The following code demonstrates changing the text of a CheckBox control when a user checks or unchecks the control. The Visual Basic 6.0 Value property is replaced by the Visual Basic 2008 Checked property, and the Caption property is replaced by the Text property. Notice that the Visual Basic 2008 example uses the CheckStateChanged event to duplicate the behavior of the Visual Basic 6.0 Click event.

' Visual Basic 6.0
Private Sub Check1_Click()
    If Check1.Value = 1 Then
        Check1.Caption = "Checked"
    Else
        Check1.Caption = "Unchecked"
    End If
End Sub

' Visual BasicPrivateSub CheckBox1_CheckStateChanged(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles CheckBox1.CheckStateChanged
    If CheckBox1.Checked = TrueThen
        CheckBox1.Text = "Checked"Else
        CheckBox1.Text = "Unchecked"EndIfEndSub

Code Changes for Determining the State of a CheckBox

The following example demonstrates checking the state of a CheckBox control at run time.

' Visual Basic 6.0
Select Case Check1.Value
    Case vbUnchecked
        Check1.Caption = "Unchecked"
    Case vbChecked
        Check1.Caption = "Checked"
    Case vbGrayed
        Check1.Caption = "Disabled"
End Select

' Visual BasicSelectCase CheckBox1.CheckState
    Case CheckState.Unchecked
        CheckBox1.Text = "Unchecked"Case CheckState.Checked
        CheckBox1.Text = "Checked"Case CheckState.Indeterminate
        CheckBox1.Text = "Disabled"EndSelect

CheckBox Control Property, Method, and Event Equivalents

The following tables list Visual Basic 6.0 properties, methods, and events, along with their Visual Basic 2008 equivalents. Those properties, methods, and events that have the same names and behaviors are not listed. Where applicable, constants are indented beneath the property or method. All Visual Basic 2008 enumerations map to the System.Windows.Forms namespace unless otherwise noted.

Links are provided as necessary to topics explaining differences in behavior. Where there is no direct equivalent in Visual Basic 2008, links are provided to topics that present alternatives.

Properties

Visual Basic 6.0 Property	Visual Basic 2008 Equivalent
Alignment 0 (Left Justify) 1 (Right Justify)	CheckAlign MiddleLeft enumeration value MiddleRight enumeration value
Appearance 0 (Flat) 1 (3D)	FlatStyle enumeration Flat enumeration value Standard enumeration value
BackColor	BackColor Note: For a list of color constants, see Color Handling for Visual Basic 6.0 Users. Note: Colors are handled differently in Visual Basic 2008. For more information, see Color Behavior for Visual Basic 6.0 Users.
Caption	Text
Container	Parent
DataChanged DataField DataFormat DataMember DataSource	New implementation. For more information, see Data Access for Visual Basic 6.0 Users.
DisabledPicture DownPicture	New implementation. For more information, see How to: Emulate a Visual Basic 6.0 Tri-State Control in an Upgraded Application.
DragIcon DragMode	New implementation. For more information, see Drag and Drop for Visual Basic 6.0 Users.
Font FontBold FontItalic FontName FontSize FontStrikethrough FontUnderline	Font Note: Fonts are handled differently in Visual Basic 2008. For more information, see Font Handling for Visual Basic 6.0 Users.
ForeColor	ForeColor Note: For a list of color constants, see Color Handling for Visual Basic 6.0 Users. Note: Colors are handled differently in Visual Basic 2008. For more information, see Color Behavior for Visual Basic 6.0 Users.
Height	Height, Size Note: Coordinates are handled differently in Visual Basic 2008. For more information, see Coordinate System for Visual Basic 6.0 Users.
HelpContextID	New implementation. For more information, see Help Support for Visual Basic 6.0 Users.
HWnd	Handle
Index	New implementation. For more information, see Control Arrays for Visual Basic 6.0 Users.
Left	Left Note: Coordinates are handled differently in Visual Basic 2008. For more information, see Coordinate System for Visual Basic 6.0 Users.
MaskColor	New implementation. For more information, see MaskColor for Visual Basic 6.0 Users.
MouseIcon	New implementation. For more information, see Cannot set a custom MousePointer.
MousePointer	Cursor For a list of constants, see MousePointer for Visual Basic 6.0 Users.
OLEDropMode	New implementation. For more information, see Drag and Drop for Visual Basic 6.0 Users.
Parent	FindForm method
Picture	Image
RightToLeft True False	RightToLeft Yes enumeration value No enumeration value
Style 0 (Standard) 1 (Graphical)	Appearance Normal enumeration value Button enumeration value Note: There are differences in how the Graphical style is handled in Visual Basic 2008. For more information, see How to: Emulate a Visual Basic 6.0 Tri-State Control in an Upgraded Application.
Tag	Tag
ToolTipText	ToolTip component For more information, see ToolTip Support for Visual Basic 6.0 Users.
Top	Top Note: Coordinates are handled differently in Visual Basic 2008. For more information, see Coordinate System for Visual Basic 6.0 Users.
UseMaskColor	New implementation. For more information, see MaskColor for Visual Basic 6.0 Users.
Value 0 (vbUnchecked) 1 (vbChecked) 2 (vbGrayed)	CheckState Unchecked enumeration value Checked enumeration value Indeterminate enumeration value
WhatsThisHelpID	New implementation. For more information, see Help Support for Visual Basic 6.0 Users.
Width	Width, Size Note: Coordinates are handled differently in Visual Basic 2008. For more information, see Coordinate System for Visual Basic 6.0 Users.

Methods

Visual Basic 6.0 Method	Visual Basic 2008 Equivalent
Drag	New implementation. For more information, see Drag and Drop for Visual Basic 6.0 Users.
Move	SetBounds Note: Coordinates are handled differently in Visual Basic 2008. For more information, see Coordinate System for Visual Basic 6.0 Users.
OLEDrag	New implementation. For more information, see Drag and Drop for Visual Basic 6.0 Users.
SetFocus	Focus
ShowWhatsThis	New implementation. For more information, see Help Support for Visual Basic 6.0 Users.
ZOrder 0 (vbBringToFront) 1 (vbSendToBack)	BringToFront, SendToBack

Events

Visual Basic 6.0 Event	Visual Basic 2008 Equivalent
Click	CheckStateChanged Note: In Visual Basic 6.0, the Click event is raised when the CheckBox state is changed programmatically. In Visual Basic 2008, the Click event is not raised; therefore, you should use the CheckStateChanged event.
DragDrop DragOver	New implementation. For more information, see Drag and Drop for Visual Basic 6.0 Users.
GotFocus	Enter
LostFocus	Leave
OLECompleteDrag OLEDragDrop OLEDragOver OLEGiveFeedback OLESetData OLEStartDrag	New implementation. For more information, see Drag and Drop for Visual Basic 6.0 Users.
Validate	Validating

Upgrade Notes

When upgrading a Visual Basic 6.0 application using the Upgrade wizard, CheckBox controls are upgraded to Windows Forms CheckBox controls, and code is updated to use equivalent properties, methods, and events. Where there are no equivalents or where there are potential behavioral differences, comments are inserted into the code with a link to a Help topic.

Dela via