PictureBox Control for Visual Basic 6.0 Users

Artikel
09/03/2015

The PictureBox control in Visual Basic 6.0 is replaced by the Windows Forms PictureBox 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

PictureBox as a Container

The Visual Basic 6.0 PictureBox control is a container control; in addition to displaying pictures it can be used to group and display other controls.

The Visual Basic 2008 PictureBox control is not a container control; it is only used to display pictures. You can use the new Panel control as a replacement for the PictureBox control where you need a container control.

AutoSize Property

In Visual Basic 6.0, the AutoSize property determines whether a PictureBox control retains its design-time size (AutoSize = False) or is resized dynamically to fit the dimensions of the picture (AutoSize = True).

In Visual Basic 2008, the AutoSize property is replaced by the SizeMode property; in addition to the Normal and AutoSize modes, options are also available to center, stretch, or zoom the picture.

Graphics Properties and Methods

In Visual Basic 6.0, various graphics properties and methods can be used to draw lines, shapes, and text on top of a PictureBox control.

In Visual Basic 2008, controls no longer have graphics properties or methods; you can still draw on top of a PictureBox control using a T:System.Drawing.Graphics object. For more information, see Graphics for Visual Basic 6.0 Users.

Other Differences

In addition, there are numerous conceptual differences that apply to all controls, including differences in data binding, font handling, drag-and-drop functionality, Help support, and more. For more information, see Windows Forms Concepts for Visual Basic 6.0 Users.

Code Changes for the PictureBox Control

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

Code Changes for Displaying a Picture

The following code demonstrates how to display a picture in a PictureBox control at run time.

' Visual Basic 6.0
Picture1.Picture = LoadPicture(App.Path & "\somepicture.jpg")

' Visual Basic
PictureBox1.Image = System.Drawing.Bitmap.FromFile( _
  My.Application.Info.DirectoryPath & "\somepicture.jpg")

Code Changes for Clearing a PictureBox Control

The following code demonstrates how to clear a PictureBox control at run time so that no image is displayed.

' Visual Basic 6.0
Picture1.Picture = LoadPicture("")

' Visual BasicIfNot (PictureBox1.Image IsNothing) Then
    PictureBox1.Image.Dispose()
    PictureBox1.Image = NothingEndIf

Code Changes for Drawing on a PictureBox Control

The following code demonstrates how to draw a 40 pixel diameter red circle in the center of a PictureBox control at run time.

' Visual Basic 6.0
Private Sub Picture1_Paint
    Dim x As Integer
    Dim y As Integer
    Picture1.ScaleMode = vbPixels
    x = Picture1.ScaleWidth / 2
    y = Picture1.ScaleHeight / 2
    Picture1.Circle (x, y), 20, vbRed
End Sub

' Visual BasicPrivateSub PictureBox1_Paint(ByVal sender AsObject, ByVal e _
As System.Windows.Forms.PaintEventArgs) Handles PictureBox1.Paint
    Dim radius AsInteger = 20
    Dim diameter AsInteger = radius * 2
    Dim x AsInteger = (PictureBox1.Width / 2) - radius
    Dim y AsInteger = (PictureBox1.Height / 2) - radius
    e.Graphics.DrawEllipse(Pens.Red, x, y, diameter, diameter)
EndSub

PictureBox Control Property, Method, and Event Equivalencies

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 name and behavior 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.

This table provides links to topics explaining behavior differences. Where there is no direct equivalent in Visual Basic 2008, links are provided to topics that present alternatives.

Properties

Visual Basic 6.0	Visual Basic 2008 Equivalent
Align	Dock
Appearance	New implementation. For more information, see Appearance and BorderStyle Properties for Visual Basic 6.0 Users.
AutoRedraw	New implementation. For more information, see Graphics for Visual Basic 6.0 Users.
AutoSize	SizeMode
BackColor	BackColor Note: Colors are handled differently in Visual Basic 2008. For more information, see Color Behavior for Visual Basic 6.0 Users.
BorderStyle	BorderStyle Note: In Visual Basic 6.0, the default is Fixed Single; in Visual Basic 2008 the default is None.
ClipControls	New implementation. For more information, see Graphics for Visual Basic 6.0 Users.
Container	Parent
CurrentX CurrentY	New implementation. For more information, see Graphics for Visual Basic 6.0 Users.
DataChanged DataField DataFormat DataMember DataSource	New implementation. For more information, see Data Access for Visual Basic 6.0 Users.
DragIcon DragMode	New implementation. For more information, see Drag and Drop for Visual Basic 6.0 Users.
DrawMode DrawStyle DrawWidth FillColor FillStyle	New implementation. For more information, see Graphics 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 Object for Visual Basic 6.0 Users.
ForeColor	ForeColor Note: Colors are handled differently in Visual Basic 2008. For more information, see Color Behavior for Visual Basic 6.0 Users.
HasDC HDC	New implementation. For more information, see Graphics 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
Image	New implementation. For more information, see Graphics for Visual Basic 6.0 Users. Note: In Visual Basic 2008, the Image property is not a graphics property. It is the equivalent of the Visual Basic 6.0 Picture property.
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.
LinkItem LinkMode LinkTimeOut LinkTopic	No equivalent. For more information, see Dynamic Data Exchange 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.
OLEDragMode OLEDropMode	New implementation. For more information, see Drag and Drop for Visual Basic 6.0 Users.
Parent	FindForm
Picture	Image
ScaleHeight ScaleLeft ScaleMode ScaleTop ScaleWidth	New implementation. For more information, see Coordinate System for Visual Basic 6.0 Users.
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.
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	Visual Basic 2008 Equivalent
Circle Cls	New implementation. For more information, see Graphics for Visual Basic 6.0 Users.
Drag	New implementation. For more information, see Drag and Drop for Visual Basic 6.0 Users.
Line	New implementation. For more information, see Graphics for Visual Basic 6.0 Users.
LinkExecute LinkPoke LinkRequest LinkSend	No equivalent. For more information, see Dynamic Data Exchange 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.
PaintPicture Point Print PSet	New implementation. For more information, see Graphics for Visual Basic 6.0 Users.
Scale ScaleX ScaleY	New implementation. For more information, see Coordinate System for Visual Basic 6.0 Users.
SetFocus	Focus
ShowWhatsThis	New implementation. For more information, see Help Support for Visual Basic 6.0 Users.
TextHeight TextWidth	New implementation. For more information, see Graphics for Visual Basic 6.0 Users.
ZOrder	BringToFront or SendToBack method

Events

Visual Basic 6.0	Visual Basic 2008 Equivalent
Change	New implementation. There are individual events (BackgroundImageChanged, SizeChanged, and so forth) that are raised when some properties are changed.
DblClick	DoubleClick
DragDrop DragOver	New implementation. For more information, see Drag and Drop for Visual Basic 6.0 Users.
GotFocus	Enter
KeyDown KeyPress KeyUp	New implementation. The Visual Basic 2008 PictureBox control is not a container control and does not receive keystrokes.
LinkClose LinkError LinkNotify LinkOpen	No equivalent. For more information, see Dynamic Data Exchange for Visual Basic 6.0 Users.
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

During upgrade, PictureBox controls that contain controls are upgraded to Panel controls. For Visual Basic 6.0 PictureBox controls that were upgraded to Panel controls, images assigned to the Picture property are mapped to the BackgroundPicture property of the Panel control.

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