UIElementCollection.Contains(UIElement) 方法

定義

命名空間:

System.Windows.Controls

組件:

PresentationFramework.dll

判斷所指定的項目是否在 UIElementCollection 中。

public:
 virtual bool Contains(System::Windows::UIElement ^ element);

public virtual bool Contains (System.Windows.UIElement element);

abstract member Contains : System.Windows.UIElement -> bool
override this.Contains : System.Windows.UIElement -> bool

Public Overridable Function Contains (element As UIElement) As Boolean

參數

element

UIElement

要尋找的元素。

傳回

Boolean

如果在集合中找到指定的 UIElement，則為 true，否則為 false。

範例

下列範例會 Contains 使用 方法來判斷 特定 UIElement 是否存在於 UIElementCollection 內。

void ContainsElement(object sender, RoutedEventArgs e)
{
    TextBlock txt1 = new TextBlock();
    sp1.Children.Add(txt1);
    txt1.Text = "This StackPanel contains UIElement btn1: " + sp1.Children.Contains(btn1).ToString();
}

Private Sub ClearButtons(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
    sp1.Children.Clear()
    btn = New Button()
    btn.Content = "Click to clear"
    sp1.Children.Add(btn)
    AddHandler btn.Click, AddressOf Me.ClearControls
    btn1 = New Button()
    btn1.Content = "Click to clear"
    sp1.Children.Add(btn1)
    AddHandler btn1.Click, AddressOf Me.ClearControls
    btn2 = New Button()
    btn2.Content = "Click to clear"
    sp1.Children.Add(btn2)
    AddHandler btn2.Click, AddressOf Me.ClearControls
    btn3 = New Button()
    btn3.Content = "Click to clear"
    sp1.Children.Add(btn3)
    AddHandler btn3.Click, AddressOf Me.ClearControls
End Sub

Private Sub ClearControls(ByVal sender As Object, ByVal e As RoutedEventArgs)
    sp1.Children.Clear()
End Sub