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ListBox.ClearSelected Method

Definition

Unselects all items in the ListBox.

public:
 void ClearSelected();
public void ClearSelected ();
member this.ClearSelected : unit -> unit
Public Sub ClearSelected ()

Examples

The following code example demonstrates how to use the SelectedIndex property with the TopIndex property to move the currently selected item to the top of the list of items in the display area of the ListBox. The example further demonstrates how to remove items using the RemoveAt method of the System.Windows.Forms.ListBox.ObjectCollection class, and how to clear all item selection using the ClearSelected method. The code first moves the currently selected item in the ListBox to the top of the list. The code then removes all items before the currently selected item and clears all selections in the ListBox. This example requires that a ListBox containing items is added to a form and that an item is currently selected in the ListBox.

private:
   void RemoveTopItems()
   {
      // Determine if the currently selected item in the ListBox 
      // is the item displayed at the top in the ListBox.
      if ( listBox1->TopIndex != listBox1->SelectedIndex )

      // Make the currently selected item the top item in the ListBox.
      listBox1->TopIndex = listBox1->SelectedIndex;

      // Remove all items before the top item in the ListBox.
      for ( int x = (listBox1->SelectedIndex - 1); x >= 0; x-- )
      {
         listBox1->Items->RemoveAt( x );
      }

      // Clear all selections in the ListBox.
      listBox1->ClearSelected();
   }
private void RemoveTopItems()
{
   // Determine if the currently selected item in the ListBox 
   // is the item displayed at the top in the ListBox.
   if (listBox1.TopIndex != listBox1.SelectedIndex)
      // Make the currently selected item the top item in the ListBox.
      listBox1.TopIndex = listBox1.SelectedIndex;

   // Remove all items before the top item in the ListBox.
   for (int x = (listBox1.SelectedIndex -1); x >= 0; x--)
   {
      listBox1.Items.RemoveAt(x);
   }

   // Clear all selections in the ListBox.
   listBox1.ClearSelected();
}
Private Sub RemoveTopItems()
   ' Determine if the currently selected item in the ListBox 
   ' is the item displayed at the top in the ListBox.
   If listBox1.TopIndex <> listBox1.SelectedIndex Then
      ' Make the currently selected item the top item in the ListBox.
      listBox1.TopIndex = listBox1.SelectedIndex
   End If
   ' Remove all items before the top item in the ListBox.
   Dim x As Integer
   For x = listBox1.SelectedIndex - 1 To 0 Step -1
      listBox1.Items.RemoveAt(x)
   Next x

   ' Clear all selections in the ListBox.
   listBox1.ClearSelected()
End Sub

Remarks

Calling this method is equivalent to setting the SelectedIndex property to negative one (-1). You can use this method to quickly unselect all items in the list.

Applies to

See also