ItemCollection.Clear Metoda

Definice

Vymaže kolekci a uvolní odkazy na všechny položky, které jsou aktuálně v kolekci.Clears the collection and releases the references on all items currently in the collection.

public:
 virtual void Clear();
public void Clear ();
abstract member Clear : unit -> unit
override this.Clear : unit -> unit
Public Sub Clear ()

Implementuje

Výjimky

ItemCollectionJe v ItemsSource režimu.The ItemCollection is in ItemsSource mode. (Pokud ItemsSource je vlastnost nastavena, bude Items kolekce provedena jen pro čtení a pevná velikost.)(When the ItemsSource property is set, the Items collection will be made read-only and fixed-size.)

Příklady

Následující příklad ukazuje, jak použít tuto metodu.The following example shows how to use this method. V příkladu sbar je StatusBar ovládací prvek, který je ItemsControl .In the example, sbar is a StatusBar control, which is an ItemsControl.

private void MakeProgressBar(object sender, RoutedEventArgs e)
{
    sbar.Items.Clear();
    TextBlock txtb = new TextBlock();
    txtb.Text = "Progress of download.";
    sbar.Items.Add(txtb);
    ProgressBar progressbar = new ProgressBar();
    progressbar.Width = 100;
    progressbar.Height = 20;
    Duration duration = new Duration(TimeSpan.FromSeconds(5));
    DoubleAnimation doubleanimation =
                               new DoubleAnimation(100.0, duration);
    progressbar.BeginAnimation(ProgressBar.ValueProperty,
                               doubleanimation);
    ToolTip ttprogbar = new ToolTip();
    ttprogbar.Content = "Shows the progress of a download.";
    progressbar.ToolTip = (ttprogbar);
    sbar.Items.Add(progressbar);
}
Private Sub MakeProgressBar(ByVal sender As Object, ByVal e As RoutedEventArgs)
    sbar.Items.Clear()
    Dim txtb As New TextBlock()
    txtb.Text = "Progress of download."
    sbar.Items.Add(txtb)
    Dim progressbar As New ProgressBar()
    progressbar.Width = 100
    progressbar.Height = 20
    Dim duration As New Duration(TimeSpan.FromSeconds(5))
    Dim doubleanimation As New DoubleAnimation(100.0, duration)
    progressbar.BeginAnimation(ProgressBar.ValueProperty, doubleanimation)
    Dim ttprogbar As New ToolTip()
    ttprogbar.Content = "Shows the progress of a download."
    progressbar.ToolTip = (ttprogbar)
    sbar.Items.Add(progressbar)
End Sub

Platí pro

Viz také