Control.PreviewMouseDoubleClick Event

Reference

Definition

Namespace:: System.Windows.Controls

Assembly:: PresentationFramework.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Occurs when a user clicks the mouse button two or more times.

public:
 event System::Windows::Input::MouseButtonEventHandler ^ PreviewMouseDoubleClick;

public event System.Windows.Input.MouseButtonEventHandler PreviewMouseDoubleClick;

member this.PreviewMouseDoubleClick : System.Windows.Input.MouseButtonEventHandler

Public Custom Event PreviewMouseDoubleClick As MouseButtonEventHandler

Event Type

MouseButtonEventHandler

Examples

The following example shows how to attach an event handler the PreviewMouseDoubleClick event.

<Button Name="btn1" Foreground="Black" 
        PreviewMouseDoubleClick="ChangeForeground">
  Foreground
</Button>

The following example shows the event handler of the PreviewMouseDoubleClick event.

void ChangeForeground(object sender, RoutedEventArgs e)
{
    if (btn1.Foreground == Brushes.Green)
    {
        btn1.Foreground = Brushes.Black;
        btn1.Content = "Foreground";
    }
    else
    {
        btn1.Foreground = Brushes.Green;
        btn1.Content = "Control foreground(text) changes from black to green.";
    }
}

Private Sub ChangeForeground(ByVal Sender As Object, ByVal e As System.Windows.Input.MouseButtonEventArgs)

    If (btn1.Foreground Is Brushes.Green) Then
        btn1.Foreground = Brushes.Black
        btn1.Content = "Foreground"
    Else
        btn1.Foreground = Brushes.Green
        btn1.Content = "Control foreground(text) changes from black to green."
    End If

End Sub

Remarks

Although this routed event seems to follow a tunneling route through an element tree, it actually is a direct routed event that is raised along the element tree by each UIElement. If you set the Handled property to true in a PreviewMouseDoubleClick event handler, subsequent PreviewMouseDoubleClick events along the route will occur with Handled set to false, but the MouseDoubleClick event will occur with Handled set to true. This is a higher-level event for control consumers who want to be notified when the user double-clicks the control and to handle the event in an application.

Control authors who want to handle mouse double clicks should use the PreviewMouseLeftButtonDown event when ClickCount is equal to two. This will cause the state of Handled to propagate appropriately in the case where another element in the element tree handles the event.

The Control class defines the PreviewMouseDoubleClick and MouseDoubleClick events, but not corresponding single-click events. To see if the user has clicked the control once, handle the MouseDown event (or one of its counterparts) and check whether the ClickCount property value is 1.

Routed Event Information


Identifier field	PreviewMouseDoubleClickEvent
Routing strategy	Direct
Delegate	MouseButtonEventHandler

Applies to

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