ListBox Control for Visual Basic 6.0 Users

Artikel
09/03/2015

The ListBox control in Visual Basic 6.0 is replaced by either the ListBox control or the CheckedListBox 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

Checked ListBox

In Visual Basic 6.0, the Style property of a ListBox control determines whether a check box is displayed next to each text item. Multiple items in the ListBox can be selected by selecting the check box beside them even if the MultiSelect property is set to False. There is no way to programmatically determine the checked state of an item; if you required this capability, you have to use a ListView control instead.

In Visual Basic 2008, the new CheckedListBox control displays check boxes next to each item; you can no longer display check boxes in the ListBox control. The CheckedListBox control allows you to programmatically determine the checked state of each item through a CheckedListBox..::.CheckedItemCollection collection.

Columns Property

In Visual Basic 6.0, the Columns property took an integer specifying the number of columns to display.

In Visual Basic 2008, the MultiColumn property takes a Boolean value, and the ColumnWidth property takes an integer specifying the width in pixels. If the width of the ListBox control is changed at run time, you may also need to set the ColumnWidth property for each column.

ItemCheck Event

In the Visual Basic 6.0 ListBox control, when the ItemCheck event was raised, the check state was already changed.

In the Visual Basic 2008 CheckedListBox control, when the ItemCheck event is raised the check state has not yet changed. You can get the pending value from the ItemCheckEventArgs argument passed to the event.

Code Changes for the ListBox Control

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

Code Changes for Adding and Removing Items in a ListBox Control

The following code demonstrates how to add and remove ListBox items.

' Visual Basic 6.0
' Add an item at the end of the list.
List1.AddItem "Tokyo"
' Insert an item at the top of the list.
List1.AddItem "Copenhagen", 0
' Remove the first item.
List1.RemoveItem 0

'Visual Basic' Add an item at the end of the list.
ListBox1.Items.Add("Tokyo")
' Insert an item at the top of the list.
ListBox1.Items.Insert(0, "Copenhagen")
' Remove the first item.
ListBox1.Items.RemoveAt(0)

Code Changes for Accessing Specific Items in a ListBox Control

The following code demonstrates how to return the value of a ListBox item.

' Visual Basic 6.0
Private Function GetItemText(i As Integer) As String
   ' Return the text of the item using the index:
   GetItemText = ListBox1.List(i)
End Function

' Visual BasicPrivateFunction GetItemText(ByVal i AsInteger) AsString   ' Return the text of the item using the index:
   GetItemText = CStr(ListBox1.Items(i))
EndFunction

Code Changes for Determining Checked Items in a CheckedListBox Control

The following code demonstrates how to determine the checked state of items in a CheckedListBox control.

' Visual Basic 6.0
' The Visual Basic 6.0 ListBox control didn't support this scenario,
' a ListView control had to be used instead.
Dim s As String
Dim i As Integer
' Loop through all items
For i = 1 To ListView1.ListItems.Count
   ' If an item is checked, add it to the string
   If ListView1.ListItems(i).Checked = True Then
      s = s & "Checked Item" & CStr(i) & " = " & _
ListView1.ListItems(i) & vbCrLf
   End If
Next
' Determine if any items are checked.
If s <> "" Then
    MsgBox s
End If

' Visual Basic' Determine if there are any items checked.If CheckedListBox1.CheckedItems.Count <> 0 Then  ' If so, loop through all checked items and print results.Dim x AsIntegerDim s AsString = ""For x = 0 To CheckedListBox1.CheckedItems.Count - 1
      s = s & "Checked Item " & CStr(x + 1) & " = " & _
      CStr(CheckedListBox1.CheckedItems(x)) & ControlChars.CrLf
  Next x
  MessageBox.Show(s)
EndIf

ListBox 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
Appearance	New implementation. For more information, see Appearance and BorderStyle Properties for Visual Basic 6.0 Users.
BackColor	BackColor Note: Colors are handled differently in Visual Basic 2008. For more information, see Color Behavior for Visual Basic 6.0 Users.
Columns	MultiColumn and ColumnWidth
Container	Parent
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.
FontFont 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.
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.
IntegralHeight	IntegralHeight
ItemData	New implementation. For more information, see ItemData property cannot be upgraded.
Left	Left Note: Coordinates are handled differently in Visual Basic 2008. For more information, see Coordinate System for Visual Basic 6.0 Users.
List	Items
ListCount	Count (List.Count)
ListIndex	SelectedIndex
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.
MultiSelect	SelectionMode
NewIndex	New implementation. For more information, see NewIndex property cannot be upgraded.
OLEDragMode OLEDropMode	New implementation. For more information, see Drag and Drop for Visual Basic 6.0 Users.
Parent	FindForm method
SelCount	Count (SelectedItem.Count)
Selected	GetSelected, SetSelected (ListBox control) GetItemChecked, SetItemChecked (CheckedListBox control)
Style	New implementation property. 0 – Standard maps to the CheckedListBox control, 1 – Checkbox maps to the CheckedListBox control.
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

Name	Visual Basic 2008 Equivalent
AddItem	Add AddRange Insert
Clear	Clear
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.
RemoveItem	Remove
SetFocus	Focus
ShowWhatsThis	New implementation. For more information, see Help Support for Visual Basic 6.0 Users.
ZOrder	BringToFront or SendToBack method

Events

Visual Basic 6.0	Visual Basic 2008 Equivalent
DblClick	DoubleClick
DragDrop DragOver	New implementation. For more information, see Drag and Drop for Visual Basic 6.0 Users.
GotFocus	Enter
ItemCheck	ItemCheck (CheckedListBox only)
LostFocus	Leave
OLECompleteDrag OLEDragDrop OLEDragOver OLEGiveFeedback OLESetData OLEStartDrag	New implementation. For more information, see Drag and Drop for Visual Basic 6.0 Users.
Scroll	New implementation. For more information, see TopIndex Property and Scroll Event for Visual Basic 6.0 Users.
Validate	Validating

Upgrade Notes

During upgrade, if the Style property of a Visual Basic 6.0 Listbox is set to 1 – Checkbox, it is upgraded to the CheckedListBox control; otherwise, it is upgraded to the ListBox control.

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