ListBox.SetSelected Method (Int32, Boolean)


The .NET API Reference documentation has a new home. Visit the .NET API Browser on to see the new experience.

Selects or clears the selection for the specified item in a ListBox.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

Public Sub SetSelected (
	index As Integer,
	value As Boolean


Type: System.Int32

The zero-based index of the item in a ListBox to select or clear the selection for.

Type: System.Boolean

true to select the specified item; otherwise, false.

Exception Condition

The specified index was outside the range of valid values.


The SelectionMode property was set to None.

You can use this property to set the selection of items in a multiple-selection ListBox. To select an item in a single-selection ListBox, use the SelectedIndex property.

The following code example demonstrates how to create a ListBox control that displays multiple items in columns and can have more than one item selected in the control's list. The code for the example adds 50 items to the ListBox using the Add method of the ListBox.ObjectCollection class and then selects three items from the list using the SetSelected method. The code then displays values from the ListBox.SelectedObjectCollection collection (through the SelectedItems property) and the ListBox.SelectedIndexCollection (through the SelectedIndices property). This example requires that the code is located in and called from a Form.

Private Sub button1_Click(sender As Object, e As System.EventArgs)
    ' Create an instance of the ListBox.
    Dim listBox1 As New ListBox()
    ' Set the size and location of the ListBox.
    listBox1.Size = New System.Drawing.Size(200, 100)
    listBox1.Location = New System.Drawing.Point(10, 10)
    ' Add the ListBox to the form.
    ' Set the ListBox to display items in multiple columns.
    listBox1.MultiColumn = True
    ' Set the selection mode to multiple and extended.
    listBox1.SelectionMode = SelectionMode.MultiExtended

    ' Shutdown the painting of the ListBox as items are added.
    ' Loop through and add 50 items to the ListBox.
    Dim x As Integer
    For x = 1 To 50
        listBox1.Items.Add("Item " & x.ToString())
    Next x
    ' Allow the ListBox to repaint and display the new items.

    ' Select three items from the ListBox.
    listBox1.SetSelected(1, True)
    listBox1.SetSelected(3, True)
    listBox1.SetSelected(5, True)

    ' Display the second selected item in the ListBox to the console.
    ' Display the index of the first selected item in the ListBox.
End Sub

.NET Framework
Available since 1.1
Return to top