Compartir a través de


AddListItem Method

Adds a new item to a ComboBox or ListBox control, optionally making it possible for you to specify the item's item ID.

Control.AddListItem(cItem [, nItemID] [, nColumn])

Parameters

  • cItem
    Specifies the item to add to the control.

  • nItemID
    Specifies an integer representing the unique ID of the item in the control. The maximum value you can specify for nItemID is 32,767.

    If you omit nItemID and the Sorted property is set to True (.T.), cItem is added in alphabetic sort order. If you omit nItemID and the Sorted property is set to False (.F.), cItem is added to the end of the list of the ComboBox or ListBox.

  • nColumn
    Specifies the column of the control to add the new item to. The default is 1.

Remarks

Applies To: ComboBox Control | ListBox Control

Use the AddItem method or AddListItem method when the RowSourceType property is set to 0 (None).

Each item added to a ComboBox or ListBox has two identification numbers assigned to it:

  • nItemID, an integer corresponding to the unique ID of the item in the control: the first item corresponds to nItemID = 1 unless another nItemID is specified.

  • nIndex, an integer corresponding to the order in which items are displayed by the control: the first item in the control corresponds to nIndex = 1.

The backslash ("\") is treated as a special character when used in the expression for an item. The following rules apply for this character:

  • You can disable an item in a list box or combo box by adding a single backslash to the beginning of the expression.

  • Any multiple of two backslashes used in the expression is displayed as a single backslash. For example, one or two backslashes used together will display as one, three or four backslashes together will display as two. The following example code contains a list box item containing a Universal Naming Convention (UNC) path. The code displays in the list box as \\MyServer\MyMachine\MyFolder.

    MyForm.List1.AddItem("\\\\MyServer\\MyMachine\\MyFolder")
    
  • If the expression begins with multiple backslashes, the item is not disabled. If you want to disable an item that begins with multiple backslashes, add a backslash and a close bracket (]) to the beginning of the item. For example, the following disables the UNC path item in the list box:

    MyForm.List1.AddItem("\]\\\MyServer\\MyMachine\\MyFolder")
    
  • To include a separator line, use a backslash followed by a hyphen as the item to add to the list box. For example, the following code adds a separator line to a list box.

    MyForm.List1.AddItem("\-")
    

Example

This example demonstrates using the AddItem and AddListItem methods to add values to the ListItem array. Both proper and improper ways of populating a combo box are shown for clarity.

PUBLIC ofrmListExamples
ofrmListExamples=NEWOBJECT("frmListExamples")
ofrmListExamples.Show
RETURN

DEFINE CLASS frmListExamples AS form

 DataSession = 2
 Top = 0
 Left = 0
 Height = 262
 Width = 325
 Caption = "List and ListItem Array Example"
 Name = "frmListExamples"

 ADD OBJECT shape1 AS shape WITH ;
  Top = 43, ;
  Left = 32, ;
  Height = 76, ;
  Width = 261, ;
  SpecialEffect = 0, ;
  Name = "Shape1"

 ADD OBJECT cbolistbad AS combobox WITH ;
  ColumnCount = 3, ;
  ColumnWidths = "100,100,50", ;
  Height = 22, ;
  Left = 111, ;
  Sorted = .T., ;
  Style = 2, ;
  TabIndex = 1, ;
  Top = 53, ;
  Width = 147, ;
  Name = "cboListBad"

 ADD OBJECT cbolistitem AS combobox WITH ;
  ColumnCount = 3, ;
  ColumnWidths = "100,100,50", ;
  Left = 34, ;
  Sorted = .T., ;
  Style = 2, ;
  TabIndex = 3, ;
  Top = 154, ;
  Name = "cboListItem"

 ADD OBJECT label1 AS label WITH ;
  FontBold = .T., ;
  Caption = "Using the List Array:", ;
  Height = 17, ;
  Left = 34, ;
  Top = 24, ;
  Width = 176, ;
  TabIndex = 7, ;
  Name = "Label1"

 ADD OBJECT label2 AS label WITH ;
  FontBold = .T., ;
  Caption = "Using the ListItem Array:", ;
  Height = 17, ;
  Left = 34, ;
  Top = 135, ;
  Width = 173, ;
  TabIndex = 8, ;
  Name = "Label2"

 ADD OBJECT cbolistgood AS combobox WITH ;
  ColumnCount = 3, ;
  ColumnWidths = "100,100,50", ;
  Height = 22, ;
  Left = 111, ;
  Sorted = .T., ;
  style = 2, ;
  TabIndex = 2, ;
  Top = 86, ;
  Width = 147, ;
  Name = "cboListGood"

 ADD OBJECT label3 AS label WITH ;
  Alignment = 1, ;
  Caption = "Wrong!", ;
  Height = 17, ;
  Left = 51, ;
  Top = 56, ;
  Width = 47, ;
  TabIndex = 9, ;
  Name = "Label3"

 ADD OBJECT label4 AS label WITH ;
  Alignment = 1, ;
  Caption = "Right!", ;
  Height = 17, ;
  Left = 58, ;
  Top = 89, ;
  Width = 40, ;
  TabIndex = 10, ;
  Name = "Label4"

 PROCEDURE cbolistbad.Init
  WITH This
   .AddItem( 'Cleveland' )
   .AddItem( 'Ohio', .NewIndex, 2 )
   .AddItem( '44122', .NewIndex, 3 )
   .AddItem( 'Caversham' )
   .AddItem( 'England', .NewIndex, 2 )
   .AddItem( 'RG4 8BX', .NewIndex, 3 )
   .AddItem( 'Buffalo' )
   .AddItem( 'New York', .NewIndex, 2 )
   .AddItem( '14228', .NewIndex, 3 )
   .AddItem( 'Milwaukee' )
   .AddItem( 'Wisconsin', .NewIndex, 2 )
   .AddItem( '43225', .NewIndex, 3 )
   .AddItem( 'International Falls')
   .AddItem( 'Minnesota', .NewIndex, 2 )
   .AddItem( '42666', .NewIndex, 3 )
  ENDWITH
 ENDPROC

 PROCEDURE cbolistitem.Init
  WITH This
   .AddListitem( 'Cleveland' )
   .AddListItem( 'Ohio', .NewItemID, 2 )
   .AddListItem( '44122', .NewItemID, 3 )
   .AddListItem( 'Caversham' )
   .AddListItem( 'England', .NewItemID, 2 )
   .AddListItem( 'RG4 8BX', .NewItemID, 3 )
   .AddListItem( 'Buffalo' )
   .AddListItem( 'New York', .NewItemID, 2 )
   .AddListItem( '14228', .NewItemID, 3 )
   .AddListItem( 'Milwaukee' )
   .AddListItem( 'Wisconsin', .NewItemID, 2 )
   .AddListItem( '43225', .NewItemID, 3 )
   .AddListItem( 'International Falls')
   .AddListItem( 'Minnesota', .NewItemID, 2 )
   .AddListItem( '42666', .NewItemID, 3 )
  ENDWITH
 ENDPROC

 PROCEDURE cbolistgood.Init
  WITH This
   .AddItem( 'Cleveland' )
   .List[.NewIndex, 2] = 'Ohio'
   .List[.NewIndex, 3] = '44122'
   .AddItem( 'Caversham' )
   .List[.NewIndex, 2] = 'England'
   .List[.NewIndex, 3] = 'RG4 8BX'
   .AddItem( 'Buffalo' )
   .List[.NewIndex, 2] = 'New York'
   .List[.NewIndex, 3] = '14228'
   .AddItem( 'Milwaukee' )
   .List[.NewIndex, 2] = 'Wisconsin'
   .List[.NewIndex, 3] = '43225'
   .AddItem( 'International Falls' )
   .List[.NewIndex, 2] = 'Minnesota'
   .List[.NewIndex, 3] = '42666'
  ENDWITH
 ENDPROC
ENDDEFINE

See Also

Reference

AddItem Method (Visual FoxPro)

Clear Method

ListIndex Property (Visual FoxPro)

ListItemID Property

RowSourceType Property

RemoveItem Method

Sorted Property

Other Resources

Methods (Visual FoxPro)

Language Reference (Visual FoxPro)