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Page.OnNavigatingFrom Method

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Called just before a page is no longer the active page in a frame.

Namespace:  System.Windows.Controls
Assembly:  System.Windows.Controls.Navigation (in System.Windows.Controls.Navigation.dll)

Syntax

'Declaration
Protected Overridable Sub OnNavigatingFrom ( _
    e As NavigatingCancelEventArgs _
)

protected virtual void OnNavigatingFrom(
    NavigatingCancelEventArgs e
)

Parameters

Remarks

You override the OnNavigatingFrom method to perform any actions on the page just before it becomes inactive.

Typically, you can use the OnNavigatingFrom method instead of creating an event handler for the Navigating event. Using the OnNavigatingFrom method is preferable because you do not have to remove the event handler from the NavigationService object to avoid object lifetime issues.

Examples

The following example shows how to override the OnNavigatingFrom method and use the NavigatingCancelEventArgs object to determine if a child window is displayed.

Partial Public Class About
    Inherits Page

    Public Sub New()
        InitializeComponent()
    End Sub

    Protected Overrides Sub OnNavigatingFrom(ByVal e As System.Windows.Navigation.NavigatingCancelEventArgs)
        If (e.Uri.ToString().Contains("/Home")) Then
            Dim surveyChildWindow As New SurveyWindow
            surveyChildWindow.Show()
        End If

        MyBase.OnNavigatingFrom(e)
    End Sub
End Class

public partial class About : Page
{
    public About()
    {
        InitializeComponent();
    }


    protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
    {
        if (e.Uri.ToString().Contains("/Home"))
        {
            SurveyWindow surveyChildWindow = new SurveyWindow();
            surveyChildWindow.Show();
        }

        base.OnNavigatingFrom(e);

    }
}

Version Information

Silverlight

Supported in: 5, 4, 3

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.