Item, Count, Clear, Remove, Add Methods

Purpose

These methods are provided for each collection. In addition, these methods exist for each Ocx control that contains a collection.

Syntax

object.Item( index )

object.Count

object.Clear

object.Remove( index )

object.Add [index], [key], [text], […]

object:Buttons, ListImages, Panels, ListItems, ColumnHeaders, Nodes, Tabs

object:ToolBar, ImageList, StatusBar, ListView, TreeView, TabStrip

index:Variant

Description

These methods and properties exist for the named collections that are a property of Ocx controls. As a shortcut, these properties and methods exist for the Ocx controls themselves as well. For instance, the ToolBar Ocx control contains a Buttons collection of Button objects. The members in the collection can either be accessed through the Buttons collection, but they are also available directly from the ToolBar Ocx. To clear the collection you can invoke the Clear method from Buttons, but also the Clear method from ToolBar; ToolBar.Buttons.Clear is identical to ToolBar.Clear.

Item(index)Specifies the position of a member of the collection. If a numeric expression, index must be a number from 1 to the value of the collection's Count property. If a string expression, index must correspond to the key argument specified when the member referred to was added to the collection. If the value provided as index doesn’t match any existing member of the collection, an error occurs. Item is the default property for a collection. Therefore, the statements are equivalent:
MyCollection(1) MyCollection.Item(1)

Count Returns a Long containing the number of items in a collection. Read-only.

ClearRemoves all objects in a collection.

Remove(index)Removes the specified item from a collection. index specifies the name or index in the collection of the object to be accessed.

AddAdds a member to a collection object. The syntax for the Add method is different for each Ocx collection.

Example

Global li As ListItem, n As Int32

OpenW 1

Ocx ListView lv = "", 10, 10, 200, 300 : .View = 3 : .GridLines = True : .FullRowSelect = True

lv.ColumnHeaders.Add , , "Column1" : lv.ColumnHeaders.Add , , "Column2"

For n = 1 To 20

lv.ListItems.Add , n , "" // Can be shortened to lv.Add ...

lv.ListItems.Item(n).AllText = "Item " & Format(n, "00") & ";" & Chr(64 + n) // Can be shortened to lv(n).AllText ...

Next n

Ocx Command cmd1 = "Remove Selected Item", 220, 10, 140, 22

Ocx Command cmd2 = "Remove all Even Items", 220, 35, 140, 22

Do : Sleep : Until IsNothing(Win_1)

Sub cmd1_Click

If lv.SelectedCount <> 0 // Make sure an item is selected

Set li = lv.SelectedItem

lv.ListItems.Remove li.Index

EndIf

EndSub

Sub cmd2_Click

Static Int32 cycle = 1

Select cycle

Case 1 // Remove Even

For n = lv.ListItems.Count DownTo 1

Set li = lv.ListItems(n) : Debug li.Key

If Even(Val(li.Key)) = True Then lv.ListItems.Remove li.Index

Next n

cmd2.Caption = "Delete remaining Items"

Case 2

lv.ListItems.Clear

EndSelect

Inc cycle