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WebBrowser.CanGoBack Property

  • Reference

Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll

Gets a value indicating whether a previous page in navigation history is available, which allows the GoBack() method to succeed.

public:
 property bool CanGoBack { bool get(); };
[System.ComponentModel.Browsable(false)]
public bool CanGoBack { get; }
[<System.ComponentModel.Browsable(false)>]
member this.CanGoBack : bool
Public ReadOnly Property CanGoBack As Boolean

Property Value

Boolean

true if the control can navigate backward; otherwise, false.

Attributes
BrowsableAttribute

Examples

The following code example demonstrates how to use the CanGoBack property to implement a Back button for the WebBrowser control similar to the one in Internet Explorer. This example requires that your form contains a WebBrowser control called webBrowser1 and a Button control called backButton.

For the complete code example, see How to: Add Web Browser Capabilities to a Windows Forms Application.

// Navigates WebBrowser1 to the previous page in the history.
void backButton_Click( System::Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
   this->WebBrowser1->GoBack();
}

// Disables the Back button at the beginning of the navigation history.
void WebBrowser1_CanGoBackChanged( System::Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
   this->backButton->Enabled = this->WebBrowser1->CanGoBack;
}

// Navigates webBrowser1 to the previous page in the history.
private void backButton_Click(object sender, EventArgs e)
{
    webBrowser1.GoBack();
}

// Disables the Back button at the beginning of the navigation history.
private void webBrowser1_CanGoBackChanged(object sender, EventArgs e)
{
    backButton.Enabled = webBrowser1.CanGoBack;
}

' Navigates webBrowser1 to the previous page in the history.
Private Sub backButton_Click( _
    ByVal sender As Object, ByVal e As EventArgs) _
    Handles backButton.Click

    webBrowser1.GoBack()

End Sub

' Disables the Back button at the beginning of the navigation history.
Private Sub webBrowser1_CanGoBackChanged( _
    ByVal sender As Object, ByVal e As EventArgs) _
    Handles webBrowser1.CanGoBackChanged

    backButton.Enabled = webBrowser1.CanGoBack

End Sub

Remarks

The WebBrowser control maintains a history list of all the Web pages visited during a browsing session. The GoBack method navigates the WebBrowser control to the previous page in this history, if one is available. Use the CanGoBack property to determine whether navigation history is available and contains a previous page. If this property is true, the GoBack method will succeed. Otherwise, calling the GoBack method will return a value of false and no navigation will occur.

You can also handle the CanGoBackChanged event to receive a notification when the CanGoBack property changes. Handling this event is useful, for example, to change the enabled state of a Back button when the WebBrowser control navigates to or leaves the beginning of the navigation history.

Applies to

See also