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NavigationService.CanGoBack Property

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

Gets a value that indicates whether there is at least one entry in the back navigation history.

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

Syntax

'Declaration
Public ReadOnly Property CanGoBack As Boolean

public bool CanGoBack { get; }

Property Value

Type: System.Boolean
true if there is at least one entry in the back navigation history; otherwise, false.

Remarks

The GoBack method throws an InvalidOperationException exception if there are no entries in the back navigation history. To determine whether there is at least one entry in the back navigation history, check the value of the CanGoBack property.

Examples

The following example shows buttons within a Silverlight page that allow forward and back navigation. The page uses the NavigationService property of the Page class to access the navigation service used by the hosting frame.

Private Sub BackNavButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
    If (NavigationService.CanGoBack) Then
        NavigationService.GoBack()
    End If
End Sub

Private Sub ForwardNavButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
    If (NavigationService.CanGoForward) Then
        NavigationService.GoForward()
    End If
End Sub

private void BackNavButton_Click(object sender, RoutedEventArgs e)
{
    if (NavigationService.CanGoBack)
    {
        NavigationService.GoBack();
    }
}

private void ForwardNavButton_Click(object sender, RoutedEventArgs e)
{
    if (NavigationService.CanGoForward)
    {
        NavigationService.GoForward();
    }
}

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.