UIElementCollection.Contains(UIElement) 方法

定义

命名空间:

System.Windows.Controls

程序集:

PresentationFramework.dll

确定指定的元素是否在 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

参数

element

UIElement

要查找的元素。

返回

Boolean

如果在集合中找到指定的 UIElement，则为 true；否则为 false。

示例

以下示例使用 Contains 方法确定 中UIElementCollection是否存在特定 UIElement 。

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